[Structure and biological functions of mammalian LEM-domain proteins].

During the process of open mitosis in higher eukaryotic cells, the nuclear envelope (NE) is disassembled and reassembled with highly organized and periodical dynamic morphological changes. Recent studies demonstrated that LEM-domain protein family mediates interactions among inner nuclear membrane, nuclear lamina protein and chromatin by interacting with barrier-to-autointegration-factor (BAF). The structure and function of the ternary complex formed by LEM-domain protein, nuclear lamina protein and BAF are dependent on each other. Moreover, the network formation based on this structure and function is critical for the development of basic biological processes of nuclear, and it plays important roles in chromatin separation in late metaphase and anaphase, NE reassembly after mitosis, morphological maintenance of nuclear and NE in interphase, regulation of DNA replication and DNA damage repair, regulation of gene expression and signaling pathway, and infection of retrovirus. Mutations in genes encoding LEM family proteins have important impacts on development and progression of laminopathic diseases and tumorigenesis. This review provides a detailed summary of structural and functional studies of the LEM family proteins.

[Characterization of novel alleles and new mutation sites of porcine MHC class II DQA].

The primers, DQAp161 and DQAp443, were designed based on the homologous region of SLA-DQA cDNA sequences and HLA-DQA genomic sequences. The 731 bp fragment of SLA-DQA including completed intron 2, the near completed exon 2 and partial exon 3 was obtained by PCR. The nucleotide sequences of the fragment of SLA-DQA were obtained with cloning and direct sequencing. Both nucleotide sequences of exon 2 and amino acid sequences of alpha 1 domain were analyzed in a pedigree. The sequence data were compared with all sequences of SLA-DQA exon 2 in GenBank. Two novel alleles, DQA-SLT 26 and DQA-TC 21-1, were found according to the above analyses. Four amino acid changes were observed among SLA-DQA haplotype c, d and DQA-SLT 26. They were Val-->Ala(60), Lys-->Glu(65), Asp-->Gly(81) and Lys-->Ile(93). Comparing the amino acids sequence of the all SLA-DQA sequences with DQA-TC 21-1 revealed that the His (94) was changed into Tyr.