Structure of a gene for a lysosomal membrane glycoprotein (LEP100). Housekeeping gene with unexpected exon organization.

摘要: Abstract Members of a recently described family glycoproteins constitute the major protein components lysosomal membrane. Changes in glycosylation patterns, redistribution to cell surface, and increased levels expression these proteins are associated, at least some cases, with differentiation, transformation, metastasis. To understand further regulation their relationships each other, we have isolated characterized gene for one proteins, LEP100, from chicken. Two overlapping clones were which contain nine exons eight introns 17-kilobase LEP 100. The 5'-flanking region contains CAAT TATAAA sequences, but do not appear be used as promoter elements. Further downstream three CCAAT boxes, no corresponding TATA represent putative Multiple apparent lack box, GC-rich composition 5' support classification LEP100 box-lacking housekeeping gene. As evidence nature gene, Northern blots RNA several adult embryonic tissues (skeletal muscle, kidney, liver, heart, gizzard, brain) revealed single message same size (about 3 kilobases) tissue. gene's range 104 7200 base pairs. Exons four disulfide-bonded loops protein, instead cysteine disulfide-linked pair is encoded by separate exon. existence sized mRNA all indicates that alternate splicing occurs. exon organization suggests it may evolved primordial cysteine-containing duplication events. It likely genes other members this diverged ancestral similar LEP100.