Posttranslational activation of bone morphogenetic protein 2 is mediated by proprotein convertase 6 during decidualization for pregnancy establishment

Sophea Heng, Sarah Paule, Belinda Hardman, Ying Li, Harmeet Singh, Adam Rainczuk, Andrew N. Stephens, Guiying Nie

Research output: Contribution to journalArticleResearchpeer-review

24 Citations (Scopus)

Abstract

Bone morphogenetic proteins (BMPs) require major posttranslational modifications to become biologically active. One such key modification is endoproteolytic cleavage of the initially synthesized nonactive precursor protein to release the mature ligand. Here we show in a physiological context of uterine stromal decidualization that BMP2 cleavage is mediated by proprotein convertase 5/6 (PC6). Decidualization is a uterine remodeling event critical for embryo implantation. Deletion orknockdownof either BMP2 or PC6 inhibits decidualization causing implantation failure and female infertility. In this study we provide biochemical and physiological evidence that PC6 proteolytically activates BMP2. We used freshly isolated primary human endometrial stromal cells and demonstrated that PC6 was the sole member of the PC family significantly up-regulated during decidualization. The precursor form of BMP2 was reduced, whereas its active form was increased during decidualization. Inhibition of PC6 activity inhibited decidualization, and this was accompanied by a total blockade of BMP2 activation. Addition of recombinant active BMP2 partially rescued the decidualization arrest caused by PC6 inhibition. PC6 processed BMP2 at the KREKR282↓ cleavage site, and mutating this site prevented the cleavage. This study thus demonstrates for the first time that the proteolytic activation and thus bioavailability of BMP2 is controlled by PC6.

Original languageEnglish
Pages (from-to)3909-3917
Number of pages9
JournalEndocrinology
Volume151
Issue number8
DOIs
Publication statusPublished - Aug 2010
Externally publishedYes

Cite this