The FK506-binding proteins (FKBPs) are a class of peptidyl-prolyl
cis/
trans isomerase enzymes, some of which can also operate as molecular chaperones. FKBPs comprise a large ubiquitous family, found
in virtually every part of the cell and involved in diverse processes from protein folding to stress response. Higher plant
genomes typically encode about 20 FKBPs, half of these found in the chloroplast thylakoid lumen. Several FKBPs in plants are
regulators of hormone signalling pathways, with important roles in seed germination, plant growth and stress response. Some
FKBP isoforms exists as homologous duplicates operating in finely tuned mechanisms to cope with abiotic stress. In order to
understand the roles of the plant FKBPs, especially in view of the warming environment, we have identified and analysed the
gene families encoding these proteins in rice using computational approaches. The work has led to identification of all FKBPs
from the rice genome, including novel high molecular weight forms. The rice FKBP family appears to have evolved by duplications
of FKBP genes, which may be a strategy for increased stress tolerance.
Keywords FKBPs - PPIases - Chloroplast - Chaperone