Xenopus laevis serum albumins are encoded in two closely related genes.
cDNA clones containing sequences complementary to Xenopus laevis albumin mRNA have been identified in a collection of cDNA clones made from poly(A)+ RNA prepared from male Xenopus laevis liver. Although all the albumin cDNA clones crosshybridise, restriction enzyme and heteroduplex analysis show that there are 2 closely related albumin mRNA sequences. The 2 albumin mRNAs are only mismatched by 8% but could be isolated by positive selection using stringent hybridization conditions. Oocytes injected with the 2 purified mRNAs, secreted either the 68,000 or 74,000 dalton albumin into the culture medium showing that the 2 albumins of X. laevis serum are encoded in the 2 closely related mRNAs. Measurements of the abundance of albumin mRNA show that the 2 albumin mRNAs together account for about 9% of total poly(A)+ RNA in male Xenopus laevis liver but the mRNA coding for the 74,000 dalton mRNA is about twice as abundant as that coding for the 68,000 dalton mRNA.
D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D004262:DNA Restriction Enzymes; D004274:DNA, Recombinant / Q000378:metabolism; D005260:Female; D005796:Genes; D008099:Liver / Q000378:metabolism; D008297:Male; D008854:Microscopy, Electron; D008970:Molecular Weight; D009693:Nucleic Acid Hybridization; D009865:Oocytes / Q000378:metabolism; D010957:Plasmids; D011061:Poly A / Q000235:genetics; D014176:Protein Biosynthesis; D012313:RNA / Q000235:genetics; D012333:RNA, Messenger; D012709:Serum Albumin / Q000235:genetics*; D014158:Transcription, Genetic; D014981:Xenopus
D004274:DNA, Recombinant; D012333:RNA, Messenger; D012709:Serum Albumin; D011061:Poly A; D012313:RNA; D004262:DNA Restriction Enzymes