Magabo K S, Horwitz J, Piatigorsky J, Kantorow M
Department of Biology, West Virginia University, Morgantown 26505, USA.
Invest Ophthalmol Vis Sci. 2000 Sep;41(10):3056-60.
To evaluate the expression of betaB(2)-crystallin mRNA and protein in rat, bovine, and human nonlens and nonocular tissues.
betaB(2)-crystallin mRNA levels were detected by RT-PCR. betaB(2)-crystallin protein was purified from rat and bovine tissues by FPLC chromatography. FPLC fractions were analyzed by immunoblotting. The identity of betaB(2)-crystallin protein, isolated from the retina, was confirmed by protein microsequencing.
betaB(2)-crystallin transcript was detected in rat brain, rat testis, and human retina by RT-PCR. betaB(2)-crystallin transcript was not found in rat lung, heart, ovary, spleen, thymus, kidney, and liver or in human brain and testis. betaB(2)-crystallin protein was partially purified from and its identity confirmed in rat brain, rat testis, and bovine retina. The bovine retinal protein was further confirmed to be authentic betaB(2)-crystallin by protein microsequencing.
These results establish that betaB(2)-crystallin mRNA and protein are expressed in tissues outside of the lens and outside of the eye including retina, brain, and testis. Extralenticular and extraocular expression of betaB(2)-crystallin, coupled with its participation in phosphorylation pathways, suggests that it has nonrefractive functions in these tissues.
评估βB(2)-晶体蛋白mRNA和蛋白在大鼠、牛和人类非晶状体及非眼部组织中的表达情况。
通过逆转录聚合酶链反应(RT-PCR)检测βB(2)-晶体蛋白mRNA水平。通过快速蛋白质液相色谱(FPLC)从大鼠和牛组织中纯化βB(2)-晶体蛋白。通过免疫印迹分析FPLC组分。通过蛋白质微量测序确认从视网膜分离的βB(2)-晶体蛋白的身份。
通过RT-PCR在大鼠脑、大鼠睾丸和人类视网膜中检测到βB(2)-晶体蛋白转录本。在大鼠肺、心脏、卵巢、脾脏、胸腺、肾脏和肝脏或人类脑和睾丸中未发现βB(2)-晶体蛋白转录本。从大鼠脑、大鼠睾丸和牛视网膜中部分纯化了βB(2)-晶体蛋白并确认了其身份。通过蛋白质微量测序进一步确认牛视网膜蛋白为真实的βB(2)-晶体蛋白。
这些结果表明βB(2)-晶体蛋白mRNA和蛋白在晶状体和眼外的组织中表达,包括视网膜、脑和睾丸。βB(2)-晶体蛋白的晶状体外和眼外表达,以及其参与磷酸化途径,表明它在这些组织中具有非屈光功能。