Gene editing technology reveals molecular mechanisms governing diatom population density signals

The intricate dynamics of diatom blooms, influenced by a myriad of external factors and internal signals, continue to fascinate scientists. After recognizing the potential role of density perception and intracellular signaling in dictating these phenomena, researchers have begun to elucidate the molecular basis of diatom population density regulation. Recently, a research team led by Prof. Wang Guangce from the Institute of Oceanology of the Chinese Academy of Sciences (IOCAS) reported the significant role of the marine diatom SLC24A in population density signal perception and regulation.

The study was published in The ISME Journal. The researchers meticulously identified and targeted potential genes involved in density signaling, culminating in the discovery of the central hub gene PtSLC24A. Two PtSLC24A knockout mutants of Phaeodactylum tricornutum were obtained using CRISPR/Cas9 gene editing technology. Intracellular Ca²⁺ concentration measurements indicated that cell density could induce Ca²⁺ responses, and knockout of PtSLC24A increased intracellular Ca²⁺ concentration. Three-dimensional structural modeling and simulation calculations of the PtSLC24A protein supported its Ca²⁺ transport function.

The results showed that high density could induce cell apoptosis, and knockout of PtSLC24A exacerbated this phenomenon. PtSLC24A also affected the expression of density-dependent genes at different cell densities. Beyond the laboratory, the ecological relevance of SLC24A was underscored by its ubiquitous distribution across the Tara Oceans sites, with expression patterns positively correlating with chlorophyll content in different marine phytoplankton taxa.