Saito Seiji, Yano Keiichi, Sharma Shweta, McMahon Heather E, Shimasaki Shunichi
Antibody Research Laboratories, Pharmaceutical Research Center, Kyowa Hakko Kogyo Co., Ltd., Tokyo 194-8533, Japan.
Protein Sci. 2008 Feb;17(2):362-70. doi: 10.1110/ps.073232608.
Bone morphogenetic protein-15 (BMP-15) is an oocyte-secreted factor critical for the regulation of ovarian physiology. When recombinant human BMP-15 (rhBMP-15) produced in human embryonic kidney 293 cells was subjected to SDS-PAGE analysis, two mature protein forms corresponding to 16 kDa (P16) and 17 kDa (P17) were observed. Despite the physiological relevance and critical function of BMP-15 in female reproduction, little is known about the structure of rhBMP-15. Here, we have analyzed the structure of the rhBMP-15 mature proteins (P16 and P17) using state-of-the-art proteomics technology. Our findings are as follows: (1) the N-terminal amino acid of P16 and P17 is pyroglutamic acid; (2) the Ser residue at the sixth position of P16 is phosphorylated; (3) P17 is O-glycosylated at Thr10; and (4) the C-terminal amino acid of P16 and P17 is truncated. These findings are the first knowledge of the structure of rhBMP-15 mature protein toward understanding the molecular basis of BMP-15 function and could provide an important contribution to the rapidly progressing research area involving oocyte-specific growth factors in modulation of female fertility.
骨形态发生蛋白-15（BMP-15）是一种由卵母细胞分泌的因子，对卵巢生理调节至关重要。当对在人胚肾293细胞中产生的重组人BMP-15（rhBMP-15）进行SDS-PAGE分析时，观察到两种对应于16 kDa（P16）和17 kDa（P17）的成熟蛋白形式。尽管BMP-15在雌性生殖中具有生理相关性和关键功能，但对rhBMP-15的结构却知之甚少。在此，我们使用最先进的蛋白质组学技术分析了rhBMP-15成熟蛋白（P16和P17）的结构。我们的发现如下：（1）P16和P17的N端氨基酸是焦谷氨酸；（2）P16第六位的Ser残基被磷酸化；（3）P17在Thr10处发生O-糖基化；（4）P16和P17的C端氨基酸被截断。这些发现是对rhBMP-15成熟蛋白结构的首次认识，有助于理解BMP-15功能的分子基础，并可为涉及卵母细胞特异性生长因子调节雌性生育力的快速发展的研究领域做出重要贡献。
