The JI
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     
 

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Kojima, T.
Right arrow Articles by Hayashi, K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Kojima, T.
Right arrow Articles by Hayashi, K.
The Journal of Immunology, 1998, 161: 3762-3766.
Copyright © 1998 by The American Association of Immunologists

Genetic Basis of Human Complement C8{alpha}-{gamma} Deficiency1

Takeshi Kojima*, Takahiko Horiuchi2,*, Hiroaki Nishizaka*, Yasuo Fukumori{dagger}, Tetsuki Amano{ddagger}, Kohei Nagasawa§, Yoshiyuki Niho* and Kenshi Hayashi

* First Department of Internal Medicine, Faculty of Medicine, Kyushu University, Fukuoka, Japan; {dagger} Department of Research, Osaka Red Cross Blood Center, Osaka, Japan; {ddagger} Third Department of Internal Medicine, Faculty of Medicine, Okayama University, Okayama, Japan; § Department of Internal Medicine, Saga Medical School, Saga, Japan; and Institute of Genetic Information, Kyushu University, Fukuoka, Japan


   Abstract
Top
 Abstract
Introduction
 Materials and Methods
 Results
 Discussion
 References
 
Deficiency of the {alpha}-{gamma} subunit of the eighth component of complement (C8{alpha}-{gamma}D) is frequently associated with recurrent neisserial infections, especially meningitis caused by Neisseria meningitidis. We here report the molecular basis of C8{alpha}-{gamma}D in two unrelated Japanese subjects. Screening all 11 exons of the C8{alpha} gene and all 7 exons of the C8{gamma} gene and their boundaries by exon-specific PCR/single-strand conformation polymorphism demonstrated aberrant single-stranded DNA fragments in exon 2 of C8{alpha} gene in case 1 and in exons 2 and 9 of C8{alpha} gene in case 2. Nucleotide sequencing of the amplified DNA fragments in case 1 revealed a homozygous single-point mutation at the second exon-intron boundary, inactivating the universally conserved 5' splice site consensus sequence of the second intron (IVS2+1G->T). Case 2 was a compound heterozygote for the splice junction mutation, IVS2+1G->T, and a nonsense mutation at Arg394 (R394X). R394X was caused by a C to T transition at nucleotide 1407, the first nucleotide of the codon CGA for Arg394, leading to a stop codon TGA. No mutations were detected in the C8{gamma} gene by our method. Our results indicate that the pathogenesis of C8{alpha}-{gamma}D might be caused by heterogeneous molecular defects in the C8{alpha} gene.


   Introduction
Top
 Abstract
 Introduction
Materials and Methods
 Results
 Discussion
 References
 
The eighth component of complement (C8) plays an important role in the function of membrane attack complex (MAC)3 that is generated on target cells upon activation of the complement system. MAC is generated by sequential addition of C5b, C6, C7, C8, and C9 molecules, which results in the transmembrane pore and eventual cell lysis. After binding to C8, C5b-7 complex, by itself transiently bound to membrane surface and nonfunctional, is endowed with the ability to cause membrane damage and polymerization of C9 that greatly accelerate MAC activity (1). C8 is a 151-kDa molecule consisting of three nonidentical polypeptide chains: {alpha} (Mr = 64 kDa), ß (Mr = 64 kDa), and {gamma} (Mr = 22 kDa) (2). Genetic studies of C8 polymorphisms established that {alpha}-{gamma} and ß are encoded at different loci (3, 4, 5). The genes for C8{alpha} and C8ß are located on chromosome 1p32 (6, 7), whereas the gene for C8{gamma} is located on chromosome 9q (8). The {alpha} and ß subunits of C8 show an overall structural homology to C6, C7, and C9 (9). The {gamma} subunit shows structural homology to protein HC (10). The {alpha} subunit is composed of 553 amino acid residues (11), has a domain that interacts with ß subunit (12), and comprises the binding site for C9 on C5b-8 (13). The {alpha} subunit also has several membrane surface-seeking domains and a possible transmembrane domain (11). The ß subunit also has a domain that interacts with target membranes and a domain that specifically mediates recognition and binding of C8 to C5b-7 (14). The {gamma} subunit is composed of 182 amino acid residues and is disulfide linked to the {alpha} subunit (10, 15). However, the {gamma} subunit is not essential for hemolytic activity, as evidenced by the fact that a C8 derivative composed of only {alpha} and ß is functionally equivalent to the normal protein (12). Individuals with inherited deficiencies of the component of MAC frequently suffer from recurrent neisserial infections, predominantly meningococcal infections of rare serotypes (16, 17, 18). Two functionally distinct C8 deficiency states have been described, depending on which of the C8 subunits ({alpha}-{gamma} or ß) is defective. The C8{alpha}-{gamma} deficiency (C8{alpha}-{gamma}D) is predominantly reported in Blacks, Hispanics, and Japanese, whereas C8ßD has been reported primarily in Caucasians (19, 20, 21). Molecular defects leading to inherited deficiencies of C8ß as well as the other components of MAC such as C5, C6, C7, and C9 have been described recently (22, 23, 24, 25, 26, 27, 28, 29). However, defects causing C8{alpha}-{gamma}D have not been reported as yet. In the present study, we investigated the genetic basis of C8{alpha}-{gamma}D in two unrelated Japanese subjects, using exon-specific PCR/single-strand conformation polymorphism (SSCP) analysis of C8{alpha} and C8{gamma} genes (30), followed by direct DNA sequencing anomalously migrating exons to identify mutations. Although there were no mutations detected in the C8{gamma} gene by this method in either case, a homozygous (case 1) and a compound heterozygous mutation (case 2) were identified in the C8{alpha} gene. A homozygous G to T transversion in the exon 2/intron 2 splice junction (IVS2+1G->T) of the C8{alpha} gene that would cause splicing error was detected in case 1. In case 2, a heterozygous mutation identical with that of case 1 as well as a heterozygous C to T transition in exon 9 at the first nucleotide of CGA codon for Arg394 (R394X) of the C8{alpha} gene were detected.


   Materials and Methods
Top
 Abstract
 Introduction
 Materials and Methods
Results
 Discussion
 References
 
C8{alpha}-{gamma}D subjects

Two unrelated individuals were included in this study. Case 1 was a 63-yr-old Japanese male who was admitted to Okayama University Hospital (Okayama, Japan) with macrocytic hyperchromic anemia. He had inactive pulmonary tuberculosis and ulcerative colitis. Total hemolytic activity (CH50) was undetectable, and a subsequent analysis of complement components revealed that C8 protein was also undetectable in his serum (<0.5 mg/dl) by single radial immunodiffusion assay. Total hemolytic activity was restored to 75% of the normal range by adding purified C8, but not by adding serum from a C8{alpha}-{gamma}D patient. Case 2 was a 42-yr-old Japanese female who was found to be C8{alpha}-{gamma}D during a large scale screening for inherited deficiencies of late acting complement components among healthy blood donors in Osaka, Japan (21). The serum C8 concentration in case 2 was below the detectable level either by hemolytic assay for C8 activity or by single radial immunodiffusion assay. The C8 hemolytic activity of case 2 was effectively restored by the addition of the purified C8{alpha}-{gamma} subunit (21). Therefore, these two cases were classified as C8{alpha}-{gamma}D. They had no history of meningitis or systemic neisserial infections. We were unable to perform family studies in either case.

PCR/SSCP analysis

The primers for exon-specific PCR for all 11 exons of the C8{alpha} gene and all 7 exons of the C8{gamma} gene were synthesized on the basis of the flanking intronic sequences (31, 32) and are listed in Table IGo and Table IIGo. Genomic DNA was purified from PBMC as previously described (33). Exon-specific PCR was conducted using 50 ng of genomic DNA as template, 0.2 µM of each primer, 25 µM dNTP including 2 µCi [{alpha}-32P]dCTP (ICN, Irvine, CA), and 0.125 U Taq polymerase in a 5-µl total reaction volume. Thirty cycles consisting of 1 min at 94°C and 2 min at 60°C were conducted using a thermal cycler PJ2000 (Perkin-Elmer/Cetus, Norwalk, CT). The PCR products were subjected to electrophoresis on 5% nondenaturing acrylamide gels at 4°C without glycerol or at 25°C containing 5% glycerol, using 45 mM Tris-borate and 1 mM EDTA buffer, pH 8.3, at 13 V/cm. DNA fragments were visualized by exposing the gels to Fuji RX5 film (Fuji, Kanagawa, Japan).


View this table:
[in this window]
[in a new window]
  		Table I. Primer sequences for the analysis of C8{alpha} gene

 

View this table:
[in this window]
[in a new window]
  		Table II. Primer sequences for the analysis of C8{gamma} gene

 
Genomic DNA sequencing of PCR fragments

DNA fragments of interest were excised from PCR/SSCP acrylamide gels, purified on SUPREC-01 columns (Takara Shuzo, Otsu, Japan), and reamplified by PCR reagent kit (Perkin-Elmer/Cetus), according to the manufacturer’s instructions, for 20 cycles consisting of 1 min at 95°C and 2 min at 60°C by using 2 µM of each primer, 200 µM dNTP, and 0.625 U Taq polymerase in a 25-µl total reaction volume. Reaction products were purified by Microcon 100 (Amicon, Beverly, MA) and directly sequenced using the Amplicycle sequencing kit (Perkin-Elmer/Cetus) and radiolabeled primers according to the manufacturer’s instructions. Primers were labeled using T4 polynucleotide kinase (New England Biolabs, Beverly, MA) and [{gamma}-32P]ATP (ICN) at 37°C for 20 min.


   Results
Top
 Abstract
 Introduction
 Materials and Methods
 Results
Discussion
 References
 
Detection of C8{alpha} and C8{gamma} gene mutation by PCR/SSCP analysis

SSCP analysis of all 11 C8{alpha} exon-specific PCR fragments resulted in the detection of aberrant bands in exon 2 of case 1 and in exons 2 and 9 of case 2. As shown in Figure 1Goa, the exon 2-specific PCR fragments of case 1 displayed two bands at 4°C without glycerol migrating differently from those of the C8-sufficient control run in parallel. Case 2 displayed the mixed pattern of case 1 and the control. Additionally, in case 2 the exon 9-specific PCR fragments displayed three bands at 4°C without glycerol, one of which migrated differently from those of C8-sufficient controls (Fig. 1Gob). Analysis of the PCR fragments of the C8 deficiency cases at 25°C with glycerol did not show any difference compared with those of controls (data not shown). These results suggest that in case 1, a homozygous C8{alpha} gene mutation, resides in exon 2, while in case 2 a compound heterozygous mutation exists in exons 2 and 9. No other aberrant bands were detected in any other exons of the C8{alpha} and C8{gamma} genes in either of the C8{alpha}-{gamma}D cases.



View larger version (46K):
[in this window]
[in a new window]
  		FIGURE 1. PCR/SSCP analysis of C8{alpha}-{gamma}D individuals. a, Exon-specific PCR/SSCP for exon 2 using genomic DNA from case 1 (lane 1), case 2 (lane 2), and a C8-sufficient control (lane C). b, Exon-specific PCR/SSCP for exon 9 using genomic DNA from case 1 (lane 1), case 2 (lane 2), and C8-sufficient control (lane C). Electrophoresis was performed in 5% polyacrylamide gel without glycerol at 4°C. Aberrantly migrating DNA fragments (fragment a) as well as those from the normal control (fragment b) were purified separately from the gel, amplified by PCR, and subjected to nucleotide sequencing.

 
Determination of the splice junction mutation in intron 2

The DNA fragment detected by PCR/SSCP analysis of C8{alpha} exon 2 from case 1 (Fig. 1Goa, fragment a) as well as the DNA fragment from a control (Fig. 1Goa, fragment b) were directly sequenced in its entirety. The nucleotide sequence was identical with that reported previously (30), except that nucleotide 308+1 was a T instead of a G (IVS2+1G->T; Fig. 2Goa). Nucleotide 308+1 is the first nucleotide of the C8{alpha} intron 2. The G to T transversion in intron 2 (IVS2+1G->T) would cause the truncation of the C8{alpha} protein by a splicing error (Fig. 2Gob). Direct sequencing of the C8{alpha} exon 2 showed that case 2 was heterozygous for the mutation IVS2+1G->T that was identified in case 1 (data not shown).



View larger version (42K):
[in this window]
[in a new window]
  		FIGURE 2. Definition of C8{alpha}-intron 2 mutation in cases 1 and 2. a, Partial nucleotide sequences of the SSCP bands. The sequences of fragment b from Figure 1Goa is identical with the corresponding sequence of the normal C8{alpha} gene. Fragment a from Figure 1Goa displays G to T transversion in exon 2/intron 2 splicing junction (IVS2+1G->T). b, Nucleotide sequence and deduced amino acid sequence (one-letter code) around the IVS2+1G->T mutation. This mutation destroys the highly conserved sequence at the 5' splice site of intron 2 of C8{alpha} gene.

 
Determination of the mutation in exon 9

Two single-stranded DNA fragments detected by PCR/SSCP analysis of the C8{alpha} exon 9 (Fig. 1Gob, fragments a and b) from case 2 were isolated from the gel and sequenced in their entirety. The nucleotide sequence of fragment b was identical with the corresponding sequence of the normal C8{alpha} gene. The nucleotide sequence of fragment a revealed C to T transition at nucleotide 1407 (Fig. 3Goa). Nucleotide 1407 is the first nucleotide of the codon CGA for Arg394 of the C8{alpha} gene. The C to T transition generates a termination codon, TGA, which would cause the truncation of the encoded C8{alpha} protein (Fig. 3Gob).



View larger version (39K):
[in this window]
[in a new window]
  		FIGURE 3. Definition of the C8{alpha}-exon 9 mutation in case 2. a, Partial nucleotide sequences of the SSCP bands. The sequence of fragment b from Figure 1Gob is identical with the corresponding sequence of the normal C8{alpha} gene. Fragment a from Figure 1Gob displays C to T transition at nucleotide 1407. b, Nucleotide sequence and deduced amino acid sequence (one-letter code) around the mutation. The translated C8{alpha} protein is truncated at amino acid residue 394 that is different from that of the native protein.

 

   Discussion
Top
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
References
 
We describe here the molecular basis of C8{alpha}-{gamma}D in two unrelated Japanese subjects. This is the first description of the molecular defects leading to C8{alpha}-{gamma}D. A homozygous splice junction mutation in the first case and a compound heterozygous mutation in the second case consisting of the same splice mutation and a nonsense mutation were shown to be the causes of the deficiency.

C8D appears to have an ethnic predominance. The C8ßD is exclusively identified in Caucasians, whereas C8{alpha}-{gamma}D has been found mostly in non-Caucasians (19, 20, 21). A review of complement deficiencies published in 1984 described 31 C8D individuals in 22 kindreds (19). Twelve of the 31 C8D subjects had one or more episodes of meningococcal disease. Among the 31 C8D subjects, six individuals in five kindreds (four Blacks and one Hispanic) were confirmed to be C8{alpha}-{gamma}D. In Japan, four C8{alpha}-{gamma}D individuals, one of whom was case 2 in the present study, were identified among sera from 145,640 healthy blood donors in Osaka (21).

To identify the molecular defects causing C8{alpha}-{gamma}D we adapted a two-step procedure with PCR-SSCP analysis as a first step followed by a second step of sequencing the aberrant bands. In the first step, all 11 exons of the C8{alpha} and the 7 exons of the C8{gamma} gene were amplified by PCR, and the resulting DNA fragments were analyzed by SSCP. This approach enabled us to detect target exons and avoid sequencing the entire coding region of the C8{alpha} and C8{gamma} genes of the deficient individuals. The strategy provides a rapid, sensitive, and simple method to investigate the whole coding region of genes and has been successfully used by our group for the molecular analysis of C6-, C7-, and C9-deficient individuals (24, 25, 29).

We have identified a possible RNA splicing defect in both cases. The mutation is a single-base G to T transversion destroying the highly conserved sequence at the 5' splice site of intron 2 of the C8{alpha} gene. Since the G at position +1 of the splice site sequence is completely conserved in eukaryotes (34), this mutation undoubtedly affects maturation of RNA. A widely accepted model for vertebrate pre-mRNA splicing proposed that exons are recognized and defined as units during early assembly by binding of splicing factors to the 3' end of the preceding intron, followed by a search for a suitable 5' donor site sequence, (C/A)AG:GT(A/G)AGT (the colon denotes the site of cleavage) (35, 36, 37). A point mutation at the 5' splice site at IVS2+1 results in two aberrant splicing patterns. The first is the activation of cryptic sites either upstream in the exon or downstream in the intron, which are ignored when the authentic splice site is present (38, 39). Such junctional abnormalities are reported in many disorders, such as ß-thalassemia (39), human cystic fibrosis (40), and muscle phosphofructokinase deficiency (41). The second pattern is exon skipping. The exon adjacent to the mutation is not recognized by the splicing factors involved in splice site selection. Exon skipping occurs if no suitable new 5' donor site can be identified by the spliceosome complex within approximately 300 bp downstream of the 3' site (42). An exon-skipping phenotype has also been demonstrated in many cases of naturally occurring mutations (43, 44, 45, 46, 47, 48). As C8{alpha} transcripts were not identified in PBMC from healthy controls or the C8D individuals (our unpublished observation), we were unable to analyze the aberrant transcripts caused by the mutation, IVS2+1G->T. Another single molecular defect identified in case 2 was a heterozygous C to T transition at the first nucleotide of the codon for Arg394 in exon 9. The mutation resulted in the generation of a termination codon. Nonsense mutations in human disease genes frequently cause severe reduction in mRNA levels and even when normally transcribed, truncated proteins are quickly degraded (49, 50, 51, 52). Even if translated, the mutant C8{alpha} gene encodes a polypeptide lacking the carboxyl-terminal 29% of the molecular size. As shown in Figure 4Go, this putative mutant C8{alpha} polypeptide in case 2 would be missing the perforin region, the epidermal growth factor-like region, and the thrombospondin region. In our two cases, no mutations were detected in the C8{gamma} gene by our method. This would be consistent with the report that the {gamma} subunit has no direct role in the hemolytic activity of C8 (12). In conclusion, our result provides evidence that like most other complement deficiencies, C8{alpha}-{gamma}D is caused by heterogeneous mutational events.



View larger version (14K):
[in this window]
[in a new window]
  		FIGURE 4. Schematic diagram of the molecular structure of normal C8{alpha} (adapted from Ref. 9) and the positions of mutations in cases 1 and 2. Modules are designated, according to the recommendations of a recent workshop (53), as follows: T1, thrombospondin, type 1; LA, low density lipoprotein receptor, type A; EG, epidermal growth factor.

 


   Footnotes
 
1 This work was supported in part by grants-in-aid from the Ministry of Education, Science, and Culture of Japan (08670522), the Fukuoka Cancer Society, and the Yokoyama Foundation. Back

2 Address correspondence and reprint requests to Dr. Takahiko Horiuchi, First Department of Internal Medicine, Faculty of Medicine, Kyushu University, Fukuoka 812-8582, Japan. E-mail address: Back

3 Abbreviations used in this paper: MAC, membrane attack complex; C8{alpha}-{gamma}D, C8{alpha}-{gamma} deficiency; SSCP, single-strand conformation polymorphism. Back

4 Throughout this paper, nucleotide and amino acid residues numbering for C8{alpha} is according to Rao et al. (11). Back

Received for publication October 21, 1997. Accepted for publication May 27, 1998.


   References
Top
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 References
 

  1. Müller-Eberhard, H. J.. 1986. The membrane attack complex of complement. Annu. Rev. Immunol. 4:503.[Medline]
  2. Steckel, E. W., R. G. York, J. B. Monahan, J. M. Sodetz. 1980. The eighth component of human complement: purification and physicochemical characterization of its unusual subunit structure. J. Biol. Chem. 255:11997.[Abstract/Free Full Text]
  3. Alper, C. A., D. Marcus, D. Raum, B. H. Petersen, T. J. Spira. 1983. Genetic polymorphism in C8 ß-chains: evidence for two unlinked genetic loci for the eighth component of human complement (C8). J. Clin. Invest. 72:1526.
  4. Raum, D., M. A. Spence, D. Balavitch, S. Tideman, A. D. Merritt, R. T. Taggart, B. H. Petersen, N. K. Day, C. A. Alper. 1979. Genetic control of the eighth component of complement. J. Clin. Invest. 64:858.
  5. Rittner, C., W. Hargesheimer, E. Mollenhauer. 1984. Population and formal genetics of human C81 ({alpha}-{gamma}) polymorphism. Hum. Genet. 67:166.[Medline]
  6. Theriault, A., E. Boyd, K. Whaley, J. M. Sodetz, J. M. Connor. 1992. Regional chromosomal assignment of genes encoding the {alpha} and ß subunits of human complement protein C8 to 1p32. Hum. Genet. 88:703.[Medline]
  7. Rogde, S., B. Olaisen, Jr T. Gedde-Dahl, P. Teisberg. 1986. The C8A and C8B loci are closely linked on chromosome 1. Annu. Hum. Genet. 50:139.
  8. Kaufman, K. M., J. V. Snider, N. K. Spurr, C. E. Schwartz, J. M. Sodetz. 1989. Chromosomal assignment of genes encoding the {alpha}, ß, and {gamma} subunits of human complement protein C8: identification of a close physical linkage between the {alpha} and the ß loci. Genomics 5:475.[Medline]
  9. Hobart, M. J., B. A. Fernie, R. G. DiScipio. 1995. Structure of the human C7 gene and comparison with the C6, C8A, C8B, and C9 genes. J. Immunol. 154:5188.[Abstract]
  10. Haefliger, J. A., D. Jenne, K. K. Stanley, J. Tschopp. 1987. Structural homology of human complement component C8{gamma} and plasma protein HC: identity of the cysteine bond pattern. Biochem. Biophys. Res. Commun. 149:750.[Medline]
  11. Rao, A. G., O. M. Howard, S. C. Ng, A. S. Whitehead, H. R. Colten, J. M. Sodetz. 1987. Complementary DNA and derived amino acid sequence of the {alpha} subunit of human complement protein C8: evidence for the existence of a separate {alpha} subunit messenger RNA. Biochemistry 26:3556.[Medline]
  12. Brickner, A., J. M. Sodetz. 1984. Function of subunits within the eighth component of human complement: selective removal of the {gamma} chain reveals it has no direct role in cytolysis. Biochemistry 23:832.[Medline]
  13. Stewart, J. L., J. M. Sodetz. 1985. Analysis of the specific association of the eighth and ninth components of human complement: identification of a direct role for the {alpha} subunit of C8. Biochemistry 24:4598.[Medline]
  14. Monahan, J. B., J. M. Sodetz. 1981. Role of the ß subunit in interaction of the eighth component of human complement with the membrane-bound cytolytic complex. J. Biol. Chem. 256:3258.[Abstract/Free Full Text]
  15. Kolb, W. P., H. J. Müller-Eberhard. 1976. The membrane attack mechanism of complement: the three polypeptide chain structure of the eighth component (C8). J. Exp. Med. 143:1131.[Abstract/Free Full Text]
  16. Fijen, C. A., E. J. Kuijper, A. J. Hannema, A. G. Sjöholm, J. P. van Putten. 1989. Complement deficiencies in patients over ten years old with meningococcal disease due to uncommon serogroups. Lancet ii:585.
  17. Tedesco, F., P. Densen, M. A. Villa, B. H. Petersen, G. Sirchia. 1983. Two types of dysfunctional eighth component of complement (C8) molecules in C8 deficiency in man: reconstitution of normal C8 from the mixture of two abnormal C8 molecules. J. Clin. Invest. 71:183.
  18. Di Ninno, V. L., V. K. Chenier. 1981. Activation of complement by neisseria meningitidis. FEMS Microbiol. Lett. 12:55.
  19. Ross, S. C., P. Densen. 1984. Complement deficiency states and infection: epidemiology, pathogenesis and consequences of neisserial and other infections in an immune deficiency. Medicine 63:243.[Medline]
  20. Tedesco, F.. 1986. Component deficiencies. 8. The eighth component. Prog. Allergy 39:295.[Medline]
  21. Inai, S., Y. Akagaki, T. Moriyama, Y. Fukumori, K. Yoshimura, S. Ohnoki, H. Yamaguchi. 1989. Inherited deficiencies of the late-acting complement components other than C9 found among healthy blood donors. Int. Arch. Allergy Appl. Immunol. 90:274.[Medline]
  22. Wang, X., D. T. Fleischer, W. T. Whitehead, D. L. Haviland, S. I. Rosenfeld, J. P. Leddy, R. Snyderman, R. A. Wetsel. 1995. Inherited human complement C5 deficiency: nonsense mutations in exons 1 (Gln1 to stop) and 36 (Arg1458 to stop) and compound heterozygosity in three African-American families. J. Immunol. 154:5464.[Abstract]
  23. Würzner, R., M. J. Hobart, B. A. Fernie, D. Mewar, P. C. Potter, A. Orren, P. J. Lachmann. 1995. Molecular basis of subtotal complement C6 deficiency: a carboxy-terminally truncated but functionally active C6. J. Clin. Invest. 95:1877.
  24. Nishizaka, H., T. Horiuchi, Z.-B. Zhu, Y. Fukumori, K. Nagasawa, K. Hayashi, R. Krumdieck, C. G. Cobbs, M. Higuchi, S. Yasunaga, Y. Niho, J. E. Volanakis. 1996. Molecular bases for inherited human complement component C6 deficiency in two unrelated individuals. J. Immunol. 156:2309.[Abstract]
  25. Nishizaka, H., T. Horiuchi, Z.-B. Zhu, Y. Fukumori, J. E. Volanakis. 1996. Genetic bases of human complement C7 deficiency. J. Immunol. 157:4239.[Abstract]
  26. Kaufmann, T., G. Hänsch, C. Rittner, P. Späth, F. Tedesco, P. M. Schneider. 1993. Genetic basis of human complement C8ß deficiency. J. Immunol. 150:4943.[Abstract]
  27. Saucedo, L., L. Ackermann, A. E. Platonov, A. Gewurz, R. M. Rakita, P. Densen. 1995. Delineation of additional genetic bases for C8ß deficiency: prevalence of null alleles and predominance of C->T transition in their genesis. J. Immunol. 155:5022.[Abstract]
  28. Witzel-Schlömp, K., P. J. Späth, M. J. Hobart, B. A. Fernie, C. Rittner, T. Kaufmann, P. M. Schneider. 1997. The human complement C9 gene: identification of two mutations causing deficiency and revision of the gene structure. J. Immunol. 158:5403.
  29. Horiuchi, T., H. Nishizaka, T. Kojima, T. Sawabe, Y. Niho, P. M. Schneider, S. Inaba, K. Sakai, K. Hayashi, C. Hashimura, Y. Fukumori. 1998. A non-sense mutation at Arg95 is predominant in complement 9 deficiency in Japanese. J. Immunol. 160:1509.[Abstract/Free Full Text]
  30. Hayashi, K.. 1991. PCR-SSCP: a simple and sensitive method for detection of mutations in the genomic DNA. PCR Methods Appl. 1:34.[Medline]
  31. Michelotti, G. A., J. V. Snider, J. M. Sodetz. 1995. Genomic organization of human complement protein C8{alpha} and further examination of its linkage to C8ß. Hum. Genet. 95:513.[Medline]
  32. Kenneth, M. K., J. M. Sodetz. 1994. Genomic structure of human complement protein C8{gamma}: homology to the lipocalin gene family. Biochemistry 33:5162.[Medline]
  33. Horiuchi, T., K. J. Macon, V. J. Kidd, J. E. Volanakis. 1989. cDNA cloning and expression of human complement component C2. J. Immunol. 142:2105.[Abstract]
  34. Horowitz, D. S., A. R. Krainer. 1994. Mechanisms for selecting 5' splice sites in mammalian pre-mRNA splicing. Trends Genet. 10:100.[Medline]
  35. Robertson, B. L., G. J. Cote, S. M. Berget. 1990. Exon definition may facilitate splice site selection in RNAs with multiple exons. Mol. Cell. Biol. 10:84.[Abstract/Free Full Text]
  36. Penotti, F. E.. 1991. Human pre-mRNA splicing signals. J. Theor. Biol. 150:385.[Medline]
  37. Iida, Y.. 1990. Quantification analysis of 5'-splice signal sequences in mRNA precursors: mutations in 5'-splice signal sequence of human ß-globin gene and ß-thalassemia. J. Theor. Biol. 145:523.[Medline]
  38. Padgett, R. A., S. M. Grabowski, M. M. Konarski, S. Seiler, P. A. Sharp. 1986. Splicing of messenger RNA precursors. Annu. Rev. Biochem. 55:1119.[Medline]
  39. Jr Kazazian, H. H.. 1990. The thalassemia syndromes: molecular basis and prenatal diagnosis in 1990. Semin. Hematol. 27:209.[Medline]
  40. Jones, C. T., I. McIntosh, M. Keston, A. Ferguson, D. J. Brock. 1992. Three novel mutations in the cystic fibrosis gene detected by chemical cleavage: analysis of variant splicing and a nonsense mutation. Hum. Mol. Genet. 1:11.[Abstract/Free Full Text]
  41. Nakajima, H., N. Kono, T. Yamasaki, K. Hotta, M. Kawachi, M. Kuwajima, T. Noguchi, T. Tanaka, S. Tarui. 1990. Genetic defect in muscle phosphofructokinase deficiency: abnormal splicing of the muscle phosphofructokinase gene due to a point mutation at the 5'-splice site. J. Biol. Chem. 265:9392.[Abstract/Free Full Text]
  42. Talerico, M., S. M. Berget. 1990. Effect of 5' splice site mutations on splicing of the preceding intron. Mol. Cell. Biol. 10:6299.[Abstract/Free Full Text]
  43. Carstens, R. P., W. A. Fenton, L. R. Rosenberg. 1991. Identification of RNA splicing errors resulting in human ornithine transcarbamylase deficiency. Am. J. Hum. Genet. 48:1105.[Medline]
  44. Marvit, J., A. G. DiLella, K. Brayton, F. D. Ledley, K. J. Robson, S. L. Woo. 1987. GT to AT transition at a splice donor site causes skipping of the preceding exon in phenylketonuria. Nucleic Acids Res. 15:5613.[Abstract/Free Full Text]
  45. Kudo, S., M. Fukuda. 1989. Structural organization of glycophorin A and B genes: glycophorin B gene evolved by homologous recombination at Alu repeat sequences. Proc. Natl. Acad. Sci. USA 86:4619.[Abstract/Free Full Text]
  46. Urlaub, G., P. J. Mitchell, C. J. Ciudad, C. J. Chasin. 1989. Nonsense mutations in the dihydrofolate reductase gene affect RNA processing. Mol. Cell. Biol. 9:2868.[Abstract/Free Full Text]
  47. Weil, D., M. Bernard, N. Combates, M. K. Wirtz, D. W. Hollister, B. Steinmann, F. Ramirez. 1988. Identification of a mutation that causes exon skipping during collagen pre-mRNA splicing in an Ehlers-Danlos syndrome variant. J. Biol. Chem. 263:8561.[Abstract/Free Full Text]
  48. Raben, N., J. Sherman, F. Miller, H. Mena, P. Plotz. 1993. A 5' splice junction mutation leading to exon deletion in an Ashkenazic Jewish family with phosphofructokinase deficiency (Tarui disease). J. Biol. Chem. 268:4963.[Abstract/Free Full Text]
  49. Losson, R., F. Lacroute. 1979. Interference of nonsense mutations with eukaryotic messenger RNA stability. Proc. Natl. Acad. Sci. USA 76:5134.[Abstract/Free Full Text]
  50. Urlaub, G., P. J. Mitchell, C. J. Ciudad, L. A. Chasin. 1989. Nonsense mutation in the dihydrofolate reductase gene affect RNA processing. Mol. Cell. Biol. 9:2868.
  51. Naeger, L. K., R. V. Schoborg, Q. Zhao, G. E. Tullis, D. J. Pintel. 1992. Nonsense mutations inhibit splicing of MVM RNA in cis when they interrupt the reading frame of either exon of the final spliced product. Genes Dev. 6:1107.[Abstract/Free Full Text]
  52. Helenius, A., T. Marquardt, I. Braakman. 1992. The endoplasmic reticulum as a protein-folding compartment. Trends Cell Biol. 2:227.[Medline]
  53. Doolittle, R. F.. 1995. The multiplicity of domains in proteins. Annu. Rev. Biochem. 64:287.[Medline]



This article has been cited by other articles:


Home page
 BloodHome page
A. Condino-Neto and P. E. Newburger
Interferon-gamma improves splicing efficiency of CYBB gene transcripts in an interferon-responsive variant of chronic granulomatous disease due to a splice site consensus region mutation
Blood, June 1, 2000; 95(11): 3548 - 3554.
[Abstract] [Full Text] [PDF]

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Kojima, T.
Right arrow Articles by Hayashi, K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Kojima, T.
Right arrow Articles by Hayashi, K.

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS