Juntipa Purintrapiban and Potchanapond Graidist

pp. 137 - 143

Abstract

Fortilin is implicated in development, cellular processes and malignant transformation. However, a unifying picture of
proteins in key processes pertaining to fortilin function is not yet emerging. To investigate the potential interactions, human
fortilin was expressed in the yeast cells, and used to screen for fortilin binding proteins in a human skeletal muscle. Yeast
cells were transformed in the sequential procedure using yeast two-hybrid expression vector (pAS2-1) containing full-length
human fortilin as ‘bait’ for the first transformation, and pGAD10 vector containing a muscle cDNA library for the second
transformation. In addition, a direct interaction of fortilin with known proteins, Ca²⁺-ATPase, creatine kinase, glycogen
phosphorylase, and troponin C was evaluated. β-Galactosidase activity was assayed as an index of interaction between
fortilin and the potential target proteins whereas yeast mating strategy was used to eliminate false positive and to reconfirm
the actual binding. From this analysis, eukaryotic translation elongation factor-1 delta (guanine nucleotide exchange protein)
was identified as a putative fortilin interacting protein.