Transcription Factor Analysis of Rhodophytes Suggests Trihelix Transcription Factors Across the Florideophyceae.

Transcription factors (TFs) are important gene transcription regulators involved in myriad functions such as development, metabolism, and stress response. TFs are found in all eukaryotes, with many families of TFs unique to plants and algae. Algae are of interest due to a wide range of novel metabolites, of which TFs play an important role in regulating their biosynthesis. In particular, the red algae (phylum Rhodophyta) are a source of several important metabolites that are a current focus of further research. However, to date, investigations of TF families in rhodophytes have been limited due to the relative lack of genomic resources available and the small number of in silico analyses of their TFs. In this study, we used genomic and transcriptomic data to identify rhodophyte TFs. We found that the general proportion of TFs in rhodophytes was overall consistent with previous research. However, for the first time in the rhodophyte class Florideophyceae, we report the presence of a putative TF within the trihelix TF (TTF) family, which are light-sensitive TFs associated with growth and stress response. In particular, we demonstrate evidence suggesting the presence of putative TTFs in three