Gordon M K, Fitch J M, Foley J W, Gerecke D R, Linsenmayer C, Birk D E, Linsenmayer T F
Department of Anatomy and Cellular Biology, Tufts University School of Medicine, Boston, Massachusetts, MA 02111, USA.
Invest Ophthalmol Vis Sci. 1997 Jan;38(1):153-66.
Previous sequence analyses of hemidesmosomal BP 180/collagen XVII cDNA from human skin and of a similar chicken corneal cDNA showed some similarities, but major differences as well. The authors examined whether, in one species, the same mRNA is present in cornea and skin. They also studied the developmental expression of the molecule and compared it to the transmembrane hemidesmosome component, alpha 6 beta 4 integrin, and to the formation of hemidesmosomes themselves.
Cornea and skin BP 180/collagen XVII cDNAs were cloned by reverse transcription-polymerase chain reaction (RT-PCR) and sequenced. Developmental expression was evaluated by quantitative RT-PCR, immunoblotting, and immunofluorescence microscopy. alpha 6 beta 4 integrin was evaluated by immunofluorescence microscopy, and hemidesmosome formation was assessed by electron microscopy.
The same alpha 1 (XVII) collagen/BP 180 mRNA is present in cornea and skin. The appearance of alpha 1 (XVII) collagen mRNA and protein shows similar temporal patterns of expression, with changes in the mRNA preceding those of the protein by approximately 2 days. The appearance of mature hemidesmosomes lags still further. Immunofluorescence histochemistry of alpha 1 (XVII) collagen and alpha 6 beta 4 integrin shows that their developmental appearance is regulated closely.
The differences between human BP 180/collagen XVII and the chicken corneal molecule represent species divergence. The appearance of alpha 1 (XVII) collagen mRNA and protein is regulated closely, with the protein lagging. Mature hemidesmosomes, once present, have a low turnover rate. The developmental appearance of alpha 1 (XVII) collagen and alpha 6 beta 4 integrin are regulated closely. However, the component responsible for initiating hemidesmosome formation remains unknown.
先前对人皮肤半桥粒BP 180/胶原蛋白XVII cDNA以及类似的鸡角膜cDNA进行的序列分析显示出一些相似性，但也存在主要差异。作者研究了在一个物种中，角膜和皮肤中是否存在相同的mRNA。他们还研究了该分子的发育表达，并将其与跨膜半桥粒成分α6β4整合素以及半桥粒本身的形成进行了比较。
通过逆转录聚合酶链反应（RT-PCR）克隆角膜和皮肤BP 180/胶原蛋白XVII cDNA并进行测序。通过定量RT-PCR、免疫印迹和免疫荧光显微镜评估发育表达。通过免疫荧光显微镜评估α6β4整合素，并通过电子显微镜评估半桥粒的形成。
角膜和皮肤中存在相同的α1（XVII）胶原蛋白/BP 180 mRNA。α1（XVII）胶原蛋白mRNA和蛋白质的出现显示出相似的时间表达模式，mRNA的变化比蛋白质的变化提前约2天。成熟半桥粒的出现则更滞后。α1（XVII）胶原蛋白和α6β4整合素的免疫荧光组织化学显示它们的发育出现受到密切调节。
人BP 180/胶原蛋白XVII与鸡角膜分子之间的差异代表物种差异。α1（XVII）胶原蛋白mRNA和蛋白质的出现受到密切调节，蛋白质滞后。成熟的半桥粒一旦形成，周转率较低。α1（XVII）胶原蛋白和α6β4整合素的发育出现受到密切调节。然而，负责启动半桥粒形成的成分仍然未知。
