[Novel complexes of gene expression and their role in the appearance and evolution of the genus Homo].

Using genetic (yeast two-hybrid system) and biochemical (co-precipitation of proteins from cellular lysates) approaches, we have performed a whole-genome wide search for interacting partners of the previously described by us variants of hRPB11 subunit of human RNA polymerase II - hRPB1 1balpha, hRPB11calpha and hRPB1 1bbeta, hRPB 11cbeta - in fetal brain and Jurkat cell line libraries. In consequence, the main spectrum of the protein partners of these human specific isoforms of the RNA polymerase II subunit hRPB 11 (POLR2J) has been established. Functional characteristics of the uncovered protein partners of hRPB 11balpha and hRPB 11calpha isoforms clearly indicate that these isoforms, similarly to the main (major) subunit hRPB11a, are components of the distinct transcription complexes participating not only in the transcription of the specific DNA matrices, but involving also in the later stages of mRNA biogenesis. The RNA polymerase I-III common subunit hRPB6 (POLR2F) and basal component of the exon-exon junction complex Y14 (RBM8A) have been found among the protein partners of the isoforms hRPB 11bbeta and hRPB 11cbeta together with a number of proteins involved in the biogenesis of microRNAs, including a novel, not previously described variant of the microRNA processing nuclease DROSHA, which indicates the existence of a special coordination between processes of transcription and RNA interference in the nuclei of human cells.

[PSM2 and POLR2J gene families as molecular markers of the higher primate evolution].

We have studied the molecular evolution of two gene families specific for primates: POLR2J of the transcription system and PMS2 of the MMR repair system. The appearance and improvement of the genetic structure in each of the families was shown to strongly correlate with the main stages of the higher primates biological evolution. Our results indicate that the PSM2 and POLR2J genes can serve as helpful and reliable molecular markers of anthropogenesis.

[New genes on human chromosome 7: bioinformatic analysis of a gene cluster from the POLR2J family]. / Novye geny na khromosome 7 cheloveka: bioinformatsionnyi analiz klastera genov iz semeistva POLR2J.

Four independent genes encoding various variants of the hRPB11 subunit of Homo sapiens RNA polymerase II were revealed in human chromosome 7. Three genes (POLR2J1, POLR2J2, and POLR2J3) form a cluster of total length 214530 bp in the genetic locus 7q22.1 on the long arm of chromosome 7 (contig NT_007933). The fourth gene (POLR2J4, 31040 bp) was localized in the cytogenetic locus 7p13 of the short arm of chromosome 7 (contig NT_007819). An analysis enabled us to refine dissimilar experimental data on the mapping of the hRPB11 subunit gene on chromosome 7. In particular, the presence of three sites of its localization according to data on hybridization with fluorescent-labeled probes (the FISH method) was explained. It was established that, upon the expression of the four human POLR2J genes, at least 14 types of mature mRNAs encoding somewhat differing hRPB11 isoforms can be synthesized. Eleven of these mRNAs were revealed (as full-length copies or clearly identifiable fragments) in the available databases of expressed sequence tags and cDNAs. The most probable scheme of origination of the multiple genes of the POLR2J family, as a result of three consecutive segmented duplications increasing in size, was proposed and substantiated. On the basis of the scheme, some assumptions on the pathways of evolution of separate human genes and the mechanisms of generation of protein diversity in higher eukaryotes were made. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 6; see also http://www.maik.ru.