Zurovec M, Vasková M, Kodrík D, Sehnal F, Kumaran A K
Entomological Institute, Academy of Sciences, Ceské Budĕjovice, Czech Republic.
Mol Gen Genet. 1995 Apr 10;247(1):1-6. doi: 10.1007/BF00425815.
The posterior section of Galleria mellonella silk glands contains two abundant mRNAs that are identical except for the non-coding tail, which includes either two (1.1 kb mRNA) or three (1.2 kb mRNA) consensus sequences for polyadenylation sites. The transcripts are 40% homologous in the coding as well as non-coding regions with the mRNA encoding light-chain fibroin (L-fibroin) in Bombyx mori; the deduced translation product shows 43% identity with the Bombyx L-fibroin peptide, with all three cysteines conserved. Amino acid analysis of the N-termini of Galleria silk proteins revealed that L-fibroin (25 kDa) occurs in two isoforms, the shorter one lacking the Ala-Pro dipeptide residue at its N-terminus. The 29 and 30 kDa Galleria silk proteins appear to be homologs of Bombyx silk component P25. The results suggest that evolutionary diversification of Galleria and Bombyx L-fibroins involves alternative polyadenylation and proteolytic processing sites.
大蜡螟丝腺的后部含有两种丰富的mRNA，它们除了非编码尾部外完全相同，非编码尾部包含两个（1.1 kb mRNA）或三个（1.2 kb mRNA）聚腺苷酸化位点的共有序列。这些转录本在编码区和非编码区与家蚕中编码轻链丝心蛋白（L-丝心蛋白）的mRNA有40%的同源性；推导的翻译产物与家蚕L-丝心蛋白肽有43%的同一性，所有三个半胱氨酸都保守。对大蜡螟丝蛋白N端的氨基酸分析表明，L-丝心蛋白（25 kDa）以两种同工型存在，较短的一种在其N端缺少丙氨酸-脯氨酸二肽残基。29 kDa和30 kDa的大蜡螟丝蛋白似乎是家蚕丝组分P25的同源物。结果表明，大蜡螟和家蚕L-丝心蛋白的进化多样化涉及可变聚腺苷酸化和蛋白水解加工位点。
