HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Repasky, J. A. E. Articles by Schatz, D. G. Search for Related Content PubMed PubMed Citation Articles by Repasky, J. A. E. Articles by Schatz, D. G. Pubmed/NCBI databases Gene GEO Profiles HomoloGene UniGene Substance via MeSH

Mutational Analysis of Terminal Deoxynucleotidyltransferase- Mediated N-Nucleotide Addition in V(D)J Recombination¹

Howard Hughes Medical Institute, Section of Immunobiology, Yale University School of Medicine, New Haven, CT 06510

The addition of nontemplated (N) nucleotides to coding ends in V(D)J recombination is the result of the action of a unique DNA polymerase, TdT. Although N-nucleotide addition by TdT plays a critical role in the generation of a diverse repertoire of Ag receptor genes, the mechanism by which TdT acts remains unclear. We conducted a structure-function analysis of the murine TdT protein to determine the roles of individual structural motifs that have been implicated in protein-protein and protein-DNA interactions important for TdT function in vivo. This analysis demonstrates that the N-terminal portion of TdT, including the BRCA-1 C-terminal (BRCT) domain, is not required for TdT activity, although the BRCT domain clearly contributes quantitatively to N-nucleotide addition activity. The second helix-hairpin-helix domain of TdT, but not the first, is required for activity. Deletional analysis also suggested that the entire C-terminal region of TdT is necessary for N-nucleotide addition in vivo. The long isoform of TdT was found to reduce N-nucleotide addition by the short form of TdT, but did not increase nucleotide deletion from coding ends in either human or rodent nonlymphoid cells. We consider these results in light of the recently reported structure of the catalytic region of TdT.

This article has been cited by other articles:

				J. M. Murray, J. P. O'Neill, T. Messier, J. Rivers, V. E. Walker, B. McGonagle, L. Trombley, L. G. Cowell, G. Kelsoe, F. McBlane, et al. V(D)J Recombinase-Mediated Processing of Coding Junctions at Cryptic Recombination Signal Sequences in Peripheral T Cells during Human Development J. Immunol., October 15, 2006; 177(8): 5393 - 5404. [Abstract] [Full Text] [PDF]