Structure and Regulation of Algal Light-Harvesting Complex Genes

Abstract

The tremendous diversity in the pigment binding ability of the light-harvesting complexes (LHCs) in different algal groups is a testament to the complex evolutionary relationships amongst them. Though all LHC genes are related and likely derived from a single ancestral gene, we broadly can place all LHCs into two categories—the chlorophyll a/b-binding and the chlorophyll a/c-binding proteins. The former category includes LHCs from the Chlorophyta, Euglenophyta and the Chloraracniophyta. The latter group encompasses antennae from the Rhodophyta, Heterokontophyta, Haptophyta, Cryptophyta and the Dinophyta. Being such an important factor in the ability of an alga to utilize the available light in a particular environment, an analysis of the LHC structure and function will provide information on the diversification of algae and the acquisition of plastids and photosynthesis and their inherent ability to acclimate to environmental changes. The different LHCs and the genes encoding them from these major eukaryotic algal divisions are reviewed with an emphasis on recent developments in gene structure, organization, regulation and evolution.