Dickinson D P, Thiesse M
University of Texas-Houston Health Science Center, Department of Basic Science, Houston 77225, USA.
Invest Ophthalmol Vis Sci. 1995 Sep;36(10):2020-31.
To examine the existence of novel protein products of the human lacrimal gland.
cDNA clones corresponding to a highly abundant human lacrimal gland mRNA were isolated and sequenced. Tissue distribution of expression was studied by Northern blot analysis, RNase protection analysis, and in situ hybridization.
A highly abundant 600-base mRNA was identified, and corresponding cDNA clones were isolated. The mRNA has a 134-residue open reading frame encoding a secreted protein of 13458 Da. This protein shows 45.5% similarity to human salivary acidic proline-rich protein PRP 1 and has a similar domain structure, but, unlike other members of the proline-rich protein family, it lacks a conserved repetitive domain. The lacrimal proline-rich protein is encoded by a single gene, designated as LPRP. Expression of LPRP was also detected in the human submandibular, von Ebners, sublingual, and parotid glands. LPRP was expressed in the acinar cells of the lacrimal gland, and in the submandibular gland expression of the LPRP and PRP 1 genes was localized to the serous acini and demilunes.
The human lacrimal gland produces a previously unknown member of the proline-rich protein family. By analogy with other proline-rich proteins, this LPRP most likely mediates protective functions in the eye, such as modulation of the microflora. In contrast to other proline-rich protein genes, LPRP is expressed in the lacrimal acinar cells, and other anterior exocrine glands. LPRP should be a useful marker for human lacrimal gland acinar cell function in vitro.
研究人类泪腺中新型蛋白质产物的存在情况。
分离并测序与人类泪腺中高丰度mRNA相对应的cDNA克隆。通过Northern印迹分析、核糖核酸酶保护分析和原位杂交研究表达的组织分布。
鉴定出一种高丰度的600个碱基的mRNA，并分离出相应的cDNA克隆。该mRNA具有一个134个残基的开放阅读框，编码一种13458 Da的分泌蛋白。这种蛋白质与人类唾液酸性富含脯氨酸蛋白PRP 1具有45.5%的相似性，并且具有相似的结构域结构，但与富含脯氨酸蛋白家族的其他成员不同，它缺乏保守的重复结构域。泪腺富含脯氨酸蛋白由单个基因编码，命名为LPRP。在人类下颌下腺、味腺、舌下腺和腮腺中也检测到了LPRP的表达。LPRP在泪腺的腺泡细胞中表达，在下颌下腺中，LPRP和PRP 1基因的表达定位于浆液性腺泡和半月形细胞。
人类泪腺产生了富含脯氨酸蛋白家族中一个此前未知的成员。与其他富含脯氨酸的蛋白质类似，这种LPRP最有可能在眼中介导保护功能，如调节微生物群落。与其他富含脯氨酸的蛋白质基因不同，LPRP在泪腺腺泡细胞和其他前分泌腺中表达。LPRP应该是体外人类泪腺腺泡细胞功能的一个有用标志物。
