Carlson D M
Department of Biochemistry and Biophysics, University of California-Davis 95616.
Biochimie. 1988 Nov;70(11):1689-95. doi: 10.1016/0300-9084(88)90304-5.
Our recent research interests have focused on a group of unusual proteins and glycoproteins high in proline content, or the so-called proline-rich proteins (PRPs). The PRPs are tissue-specific expressions of salivary gland multigene families. Normally PRPs are not detected or are present in very low amounts in rat, mouse and hamster salivary glands, but these unusual proteins are dramatically induced by treatment with the catecholamine isoproterenol. The structures and organizations of several PRP mRNAs and PRP genes have been determined. The amino acid sequences of all PRPs show 4 distinct regions, namely, a signal peptide, a transition region, a repeat region and a carboxyl-terminal region. Glycoproteins induced by isoproterenol treatment may be N-glycosylated or O-glycosylated. The N-glycosylated glycoprotein GP-158 from rat submandibular glands has a 12 amino acid glycopeptide which repeats possibly 49 times. Proline-rich proteins of the parotid glands of rats and mice are also greatly induced by dietary tannins. The apparent unique occurrence of PRPs in saliva suggests that one biological role is to neutralize the detrimental effects of dietary tannins and other polyphenols. The upstream regions of the mouse and hamster PRP genes contain cyclic AMP-regulated sequences as demonstrated by deletions and transient transfections. The PRP multigene family members of mouse are all located on chromosome 8.
我们近期的研究兴趣集中在一组富含脯氨酸的特殊蛋白质和糖蛋白，即所谓的富含脯氨酸蛋白（PRPs）。PRPs是唾液腺多基因家族的组织特异性表达产物。正常情况下，PRPs在大鼠、小鼠和仓鼠的唾液腺中无法检测到或含量极低，但用儿茶酚胺异丙肾上腺素处理后，这些特殊蛋白质会被显著诱导产生。几种PRP mRNA和PRP基因的结构及组织形式已被确定。所有PRPs的氨基酸序列都显示出4个不同区域，即信号肽、过渡区、重复区和羧基末端区。异丙肾上腺素处理诱导产生的糖蛋白可能是N-糖基化或O-糖基化的。来自大鼠下颌下腺的N-糖基化糖蛋白GP-158有一个12个氨基酸的糖肽，可能重复49次。大鼠和小鼠腮腺中的富含脯氨酸蛋白也会被膳食单宁显著诱导产生。PRPs在唾液中明显独特的存在表明其一个生物学作用是中和膳食单宁和其他多酚的有害影响。通过缺失和瞬时转染证明，小鼠和仓鼠PRP基因的上游区域包含环磷酸腺苷调节序列。小鼠的PRP多基因家族成员都位于8号染色体上。
