Theodor L, Peleg D, Meyuhas O
Biochim Biophys Acta. 1985 Nov 13;826(2-3):137-46. doi: 10.1016/0167-4781(85)90119-8.
The primary structure of P31, a 13.300 kDa mammalian 'housekeeping' protein, was deduced from the nucleotide sequence of a rat recombinant cDNA clone. The P31 mRNA has 950 nucleotides and codes for a protein of 121 amino acids. This mRNA is present in several mouse tissues and in other mammals. Nuclei of rapidly growing cells contain mature P31 mRNA and a distinctive set of larger transcripts. P31 is encoded by a multigene family. Five members of the family were isolated from a mouse genomic library and restriction mapping and S1 nuclease analysis of four of them (P31-4, P31-12, P31-13 and P31-14) suggest that they are processed genes. The very low homology of the fifth (P31-8) with respect to the corresponding cDNA sequence indicates that it is a pseudogene. Although the features of the mRNA and the genes encoding P31 exhibit extensive similarity with those of ribosomal proteins, neither the identity nor the biological function of the protein has yet been determined.
P31是一种13.300千道尔顿的哺乳动物“管家”蛋白，其一级结构由大鼠重组cDNA克隆的核苷酸序列推导得出。P31信使核糖核酸（mRNA）有950个核苷酸，编码一个由121个氨基酸组成的蛋白质。这种mRNA存在于几种小鼠组织以及其他哺乳动物中。快速生长细胞的细胞核含有成熟的P31 mRNA以及一组独特的更大的转录本。P31由一个多基因家族编码。该家族的五个成员从一个小鼠基因组文库中分离出来，对其中四个成员（P31 - 4、P31 - 12、P31 - 13和P31 - 14）进行限制酶切图谱分析和S1核酸酶分析表明它们是加工基因。第五个成员（P31 - 8）与相应cDNA序列的同源性非常低，表明它是一个假基因。尽管P31的mRNA和编码基因的特征与核糖体蛋白的特征有广泛的相似性，但该蛋白的身份及其生物学功能尚未确定。
