stf-1

Pleckstrin Homology-Like Domain Family A Member 2 (PHLDA2) is a peripheral membrane protein that belongs to the PHLDA2 family. PHLDA2 is expressed in the placenta and adult prostate gland. In the placenta, it is present in all cells of the villous cytotrophoblast. PHLDA2 plays a role in regulating placenta growth. PHLDA2 may act via its PH domain that competes with other PH domain-containing proteins, thereby preventing their binding to membrane lipids.

Cystatin-A, also known as Cystatin-AS, Stefin-A and CSTA, is a cytoplasm protein which belongs to thecystatin family. Cystatin-A / CSTA is a cysteine proteinase inhibitor with a molecular mass of 11 kDa, and is located mainly in the keratohyaline granules of the stratum granulosum and the cornified envelope of the stratum corneum in the epidermis. The cystatins are a family of cysteine protease inhibitors with homology to chicken cystatin. Cystatins are physiological inhibitors of cysteine proteinases which are widely distributed in human tissues and fluids. Cystatins typically comprise about 115 amino acids, are largely acidic, contain four conserved cysteine residues known to form two disulfide bonds. Cystatins may be glycosylated and / or phosphorylated, with similarity to fetuins, kininogens, stefins, histidine-rich glycoproteins and cystatin-related proteins. Some of the members are active cysteine protease inhibitors, while others have lost or perhaps never acquired inhibitory activity. Cystatins mainly inhibit peptidases belonging to peptidase families C1 (papain family) and C13 (legumain family).