Tamura H O, Harada Y, Miyawaki A, Mikoshiba K, Matsui M
Kyoritsu College of Pharmacy, 1-5-30, Shibakoen, Minato-ku, Tokyo 105, Japan.
Biochem J. 1998 May 1;331 ( Pt 3)(Pt 3):953-8. doi: 10.1042/bj3310953.
Previously we demonstrated the presence of phenol sulphotransferase (P-ST) in mouse nasal cytosols and identified its zonal location in mouse nasal cavity by staining with an antiserum raised against a rat liver P-ST isoenzyme, PSTg. In the present study a cDNA was isolated from a mouse olfactory cDNA library by immunological screening with the antiserum. The isolated cDNA consisted of 1347 bp with a 912 bp open reading frame encoding a 304-residue polypeptide. Both the nucleotide and deduced amino acid sequences of the cDNA were 94% identical with those of a rat liver P-ST isoenzyme, ST1C1. The expressed enzyme in Escherichia coli displayed high P-ST activity towards phenolic odorants such as eugenol and guaiacol, and it showed a high N-hydroxy-2-acetylaminofluorene sulphation activity in comparison with the rat ST1C1 enzyme. These results indicate that the olfactory P-ST encoded by the cDNA is a mouse orthologue of rat ST1C1; however, expression of the olfactory P-ST mRNA is specific for nasal tissues as revealed by reverse transcriptase-mediated PCR (RT-PCR).
此前我们已证实在小鼠鼻腔胞质溶胶中存在酚磺基转移酶(P-ST),并通过用针对大鼠肝脏P-ST同工酶PSTg产生的抗血清进行染色,确定了其在小鼠鼻腔中的区域定位。在本研究中,通过用该抗血清进行免疫筛选,从小鼠嗅觉cDNA文库中分离出一个cDNA。分离出的cDNA由1347个碱基对组成,有一个912个碱基对的开放阅读框,编码一个304个残基的多肽。该cDNA的核苷酸序列和推导的氨基酸序列与大鼠肝脏P-ST同工酶ST1C1的序列均有94%的同一性。在大肠杆菌中表达的该酶对丁香酚和愈创木酚等酚类气味剂表现出较高的P-ST活性,并且与大鼠ST1C1酶相比,它表现出较高的N-羟基-2-乙酰氨基芴硫酸化活性。这些结果表明,由该cDNA编码的嗅觉P-ST是大鼠ST1C1的小鼠同源物;然而,如逆转录酶介导的PCR(RT-PCR)所示,嗅觉P-ST mRNA的表达对鼻组织具有特异性。