Lefrère V, Vincent A, Amalric F
Centre de Recherches de Biochimie et de Génétique Cellulaires du CNRS, Université Paul Sabatier, Toulouse, France.
Gene. 1990 Dec 15;96(2):219-25. doi: 10.1016/0378-1119(90)90256-q.
Two classes of cDNAs encoding the Drosophila melanogaster (poly(A)-binding protein (PABP), which differ in length due to different positions of their respective 3' ends, were isolated by screening an embryonic cDNA library. These cDNAs hybridize to a single chromosomal site at position 55B on the right arm of the second chromosome. A unique 3.8-kb PABP mRNA species was detected, indicating that 'long' cDNAs correspond to full-length cDNAs and that the 3'-untranslated region of the D. melanogaster mRNA is close to 1.5 kb long. The PABP transcript accumulates in oocytes, is maternally inherited by the embryo and present at every other developmental stage tested. The D. melanogaster PABP cDNAs contain a 1722-nt ORF encoding a 64-kDa protein. This protein contains four RNA-binding domains which show limited primary sequence divergence during evolution, in contrast to the C-terminal third of the protein. The strikingly long 3'-untranslated region of the D. melanogaster PABP mRNA is shown to exist also in other eukaryotes including vertebrate species. It suggests that important regulatory sequences intrinsic to the PABP mRNA are present within this 3'-untranslated region.
通过筛选果蝇胚胎cDNA文库，分离出了两类编码黑腹果蝇聚腺苷酸结合蛋白（PABP）的cDNA，它们因各自3'端位置不同而长度各异。这些cDNA与第二条染色体右臂55B位置的单个染色体位点杂交。检测到一种独特的3.8 kb PABP mRNA，这表明“长”cDNA对应全长cDNA，且黑腹果蝇mRNA的3'非翻译区长度接近1.5 kb。PABP转录本在卵母细胞中积累，由胚胎母系遗传，并存在于所检测的其他每个发育阶段。黑腹果蝇PABP cDNA包含一个1722 nt的开放阅读框，编码一个64 kDa的蛋白质。该蛋白质含有四个RNA结合结构域，与蛋白质的C端三分之一相比，它们在进化过程中一级序列差异有限。黑腹果蝇PABP mRNA显著长的3'非翻译区在包括脊椎动物物种在内的其他真核生物中也存在。这表明PABP mRNA固有的重要调控序列存在于该3'非翻译区内。
