Biochemical and structural analysis on the molecular interaction between FK-506 binding protein (FKBP) 38 and anti-apoptotic protein BCL-2

Abstract

FK506 binding protein (FKBP) 38, which is a tripartite TPR domain-containing member in the FKBP family, can help Bcl-2 localize at the mitochondrial membrane and modulate apoptosis. The regulation of Bcl-2 function by forming heterodimeric complexes with its pro-apoptotic partners is well studied. Bcl-2 is also regulated at the posttranslational level through phosphorylation of specific residues within the flexible loop. Bcl-2 contains an unusually long loop between the first and the second helices. This loop has been shown to be highly flexible based on NMR and X-ray crystallographic analyses of this region. Currently, the molecular basis of alternative regulatory mechanism of Bcl-2 remains poorly understood.