Implication of RNA splicing in heat stress responses and expression of a novel trypsin-like protease in the marine diatom Chaetoceros compressum

Abstract

One explanation for the predominance of diatoms in marine ecosystem is their high adaptability to different environmental conditions. However, little is known about the physiological mechanisms concerned at the molecular level. Recent works on heat stress responses of various diatom species have indicated that diatoms markedly change their gene expression profiles and produce various molecules to respond to heat stress. Recently, we have isolated a novel heat-stress-responsive gene, Hl-5, from the marine diatom Chaetoceros compressum. Two types of transcripts were produced from the single Hl-5 gene by heat stress-dependent RNA splicing, encoding structurally different proteins, the functions of which are apparently different. This gene may be a promising molecule to give us a new insight for better understanding of heat stress responses in diatoms.