RESUMEN
The 5' region of the mouse kappa locus comprises 63 Vkappa genes in six contigs of together 1.5 Mb, including one which links the region to the central part of the locus. The structures of the contigs were established by detailed restriction mapping of cosmid clones prepared from libraries of mouse C57BL/6 DNA and of yeast and bacterial artificial chromosomes (YACs, BACs with mouse DNA inserts). Pulsed-field gel electrophoresis of yeast artificial chromosome digests indicated that the gaps between the contigs were 10 to 60 kb, comprising together about 160 kb. The region of the kappa locus described here contains Vkappa1, Vkappa2, Vkappa9/10, Vkappa11, Vkappa12/13, Vkappa20, Vkappa24, Vkappa32, Vkappa33/34 and Vkappa38C genes as well as the VkappaRF gene and, towards the center of the locus, a number of Vkappa4/5 genes. Near the 5' end of the locus interspersed alpha-tubulin gene-like sequences were found. At its 3' side the region borders on the Vkappa4/5 contigs of the central region of the locus which is described in the accompanying report (Eur. J. Immunol. 1999. 29: 2057-2064). Structural details are to be found in the Internet at http://www.med.uni-muenchen.de/biochemie/zach au/kappa.htm. In a concluding section the main features of the structure of the mouse kappa locus are summarized.
Asunto(s)
Genes de Inmunoglobulinas , Cadenas kappa de Inmunoglobulina/genética , Animales , Secuencia de Bases , Cromosomas Artificiales de Levadura/genética , Cromosomas Bacterianos/genética , Mapeo Contig , Cartilla de ADN/genética , Ratones , Datos de Secuencia Molecular , Familia de Multigenes , Mapeo RestrictivoRESUMEN
A detailed restriction map of a 430-kb contig comprising the single Ckappa, the 5 Jkappa and the adjoining 22 Vkappa gene segments is presented. The first 12 Vkappa genes following the JkappaCkappa region belong to the Vkappa21 family, the subsequent ones to the closely related families Vkappa8 and Vkappal 9/ 28. Previous difficulties in cloning all Vkappa21 genes can now be explained by the presence of a duplicated region in this part of the locus. The structure was established by analysis of yeast artificial chromosome, bacterial artificial chromosome and cosmid clones and by the so-called long template PCR technique. The distance between Ckappa and the proximal Vkappa21 gene is 22 kb and the average distances between the Vkappa genes are about 20 kb. Of the 12 Vkappa21 genes 5 were sequenced for the first time and 8 of the 12 genes were found to be expressed. Of the 10 Vkappa8 and Vkappa19/28 germline genes 9 are new; expression products of 8 of the 10 genes were known. The known 5', 3' polarities allow to specify for the 22 Vkappa genes whether they are rearranged to the JkappaCkappa element by a deletion or an inversion mechanism. Also the formation of interesting rearrangement products in classical cell lines as MPC11, MOPC41 and PC 7043 can be explained now. The non-Vkappa sequence L10 whose rearrangement by inversion has been described earlier (Hoechtl and Zachau, Nature 1983. 302: 260-263) was now localized downstream of JkappaCkappa.