I have been interested in the molecular biology of cyanobacteria for over 25 years. My interests have ranged from the specific (DNA rearrangements during heterocyst differentiation) to the more general (the biochemistry of transcription and the regulation of gene expression). Along the way, I have taken brief excursions to examine photosynthesis genes, globin genes, amino acid transport genes, and repetitive sequence elements in cyanobacteria. Most recently, studies in my lab have centred on the cyanobacterial RNA-binding proteins and their function.

An early project in my lab involved the isolation of clones of the nitrogen fixation gene, nifH, from different cyanobacteria so that their promoter sequences could be compared. However, one of the clones also contained a small open reading frame which encoded an unusual RNA-binding protein. We identified that there were many copies of these genes in cyanobacteria and especially in the heterocyst-forming cyanobacteria. Tom Belbin cloned and sequenced one of these genes from in Synechococcus sp. PCC 7942 and he then went on to examine its function through mutagenesis. Characterization of mutants showed that they were cold-sensitive indicating that the RNA-binding proteins were required for growth at low temperatures.

We tried to identify whether any specific RNA molecules are bound by these RNA-binding proteins but were unable to identify any. This remains a question of interest.