The Caenorhabditis elegans Behavioral Gene unc-24 Encodes a Novel Bipartite Protein Similar to Both Erythrocyte Band 7.2 (Stomatin) and Nonspecific Lipid Transfer Protein

Abstract: We report here the positional cloning and molecular characterization of the unc-24 gene of Caenorhabditis elegans . This gene is required for normal locomotion and interacts with genes that affect the worm's response to volatile anesthetics. The predicted gene product contains a domain similar to part of two ion channel regulators (the erythrocyte integral membrane protein stomatin and the C. elegans neuronal protein MEC-2) juxtaposed to a domain similar to nonspecific lipid transfer protein (nsLTP; also called sterol carrier protein 2). Sequence analysis suggests that the nsLTP-like domain of UNC-24 provides lipid carrier function and is tethered to the plasma membrane by the stomatin-like domain, which may be regulatory. We postulate that UNC-24 may be involved in lipid transfer between closely apposed membranes.     

Molecular Cloning of emip,a Member of the Major Intrinsic Protein (MIP) Gene Family,Preferentially Expressed in Epidermal Cells of Barley Leaves

Cloning and characterization of a barley gene named emip is reported that encodes a member of the major intrinsic protein family. A λ-unizap cDNA library synthesized from poly A⁺?mRNA of leaf epidermis was screened differentially with epidermis-versus mesophyll-derived probes. One of the clones epi 3-2 was sequenced and further analyzed. The open reading frame of the full length clone codes for a polypeptide of 288 amino acids with a molecular mass of 30,634 Da exhibiting a high degree of homology with members of the major intrinsic protein family. Hydropathy analysis predicts six potential membrane-spanning helices. mRNA levels were high in the growing zone of barley leaves and declined towards the tip of the fully expanded leaf blade. Expression was high in epidermal strips, lower in roots and very low in the leaf mesophyll. In order of decreasing response, wilting, salt shock and heat shock resulted in stimulated expression. mRNA levels remained low during slow salting up experiments. The expressional pattern suggests a role of EMIP in turgor regulation, particularly under stress.     

SNF2家族新成员Ercc61的cDNA克隆与表达分析

SNF2家族蛋白在基因组复制、修复与表达中具有重要作用.报道了SNF2家族新成员Ercc61(excision repair crosscomplementing rodent repair deficiency,complementation group 6-like)的cDNA克隆、特性与表达分析.通过表达序列标签(EST)搜索和组装,获得了cDNA全长4002 bp的新基因Ercc6l(GenBank Acc.No AY172688),然后通过RT-PCR在小鼠胚胎心脏成功克隆了该基因.Ercc6l在小鼠基因组中由两个外显子和一个内含子组成,定位于X染色体,最大开放阅读框(ORF)编码一个含l 240个氨基酸的假定蛋白质.该假定蛋白质含有SNF2蛋白的8个保守基序(SNF2结构域).通过与SNF2家族各亚家族的成员进行多重比对,初步确认Ercc6l属于ERCC6亚家族成员.将Ercc6l编码区克隆到pEGFP-C3然后转染HeLa,3T3和B16细胞,融合蛋白主要定位于胞浆.BLAST搜索检索出69条小鼠EST与Erccol同源,这些EST主要来自胚胎和肿瘤组织.对小鼠不同发育时期的多种组织进行RT-PCR,发现Ercc6l在胚胎期强表达,出生产后表达显著下调.这些结果提示Ercc6l在胚胎发育和肿瘤发生中可能具有重要作用.     

SNF2家族新成员Ercc6l的cDNA克隆与表达分析(英)

SNF2家族蛋白在基因组复制、修复与表达中具有重要作用. 报道了SNF2家族新成员Ercc6l (excision repair cross-complementing rodent repair deficiency, complementation group 6-like)的cDNA克隆、特性与表达分析.通过表达序列标签（EST）搜索和组装,获得了cDNA全长4 002 bp的新基因Ercc6l(GenBank Acc.No AY172688),然后通过RT-PCR在小鼠胚胎心脏成功克隆了该基因.Ercc6l在小鼠基因组中由两个外显子和一个内含子组成,定位于X染色体,最大开放阅读框（ORF）编码一个含1 240个氨基酸的假定蛋白质.该假定蛋白质含有SNF2蛋白的8个保守基序（SNF2结构域）.通过与SNF2家族各亚家族的成员进行多重比对,初步确认Ercc6l属于ERCC6亚家族成员.将Ercc6l编码区克隆到pEGFP-C3然后转染HeLa,3T3 和B16细胞,融合蛋白主要定位于胞浆.BLAST搜索检索出69条小鼠EST与Ercc6l同源,这些EST主要来自胚胎和肿瘤组织.对小鼠不同发育时期的多种组织进行RT-PCR,发现Ercc6l在胚胎期强表达,出生产后表达显著下调.这些结果提示Ercc6l在胚胎发育和肿瘤发生中可能具有重要作用.