The Light-Harvesting Chlorophyll a/b-Binding Polypeptides and Their Genes in Angiosperm and Gymnosperm Species

Abstract

The Chl a/b-binding (CAB) polypeptides are a set of structurally and evolutionarily related proteins found in the thylakoid membranes of chloroplasts. They form supramolecular structures known as Light-Harvesting Complexes (LHCs), where light energy is absorbed and is converted into excitation energy. There are ten distinct types of CAB polypeptides, and they are encoded by nuclear genes collectively designated as Lhc genes. Here we describe the characteristics of each type of CAB polypeptide. We also discuss the possible evolutionary processes that gave rise to the CAB family and some of the regulatory aspects of the patterns of expression of the Lhc genes.