Identification and characterization of a heat shock transcription factor in the marine red alga Pyropia yezoensis (Rhodophyta)

• Published in: Journal of applied phycology Vol. 37; no. 1; pp. 515 - 526
• Main Authors: Wi, Jiwoong, Choi, Dong-Woog
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.02.2025; Springer Nature B.V
• Subjects: Algae; Angiosperms; Aquatic plants; Biomedical and Life Sciences; Chlamydomonas; Desiccation; DNA; domain; Ecology; family; Freshwater & Marine Ecology; Genes; genetically modified organisms; Growth conditions; Growth rate; Heat; Heat shock; Heat shock factors; Heat shock proteins; Heat stress; Heat tolerance; High temperature; Intertidal environment; Intertidal zone; Life cycle; Life cycles; Life Sciences; littoral zone; Oligomerization; phylogeny; Plant Physiology; Plant Sciences; Pyropia yezoensis; Rhodophyta; Temperature; transactivators; Transcription factors; Heat shock transcription factor; Heat stress; PyHSF; Red algae
• ISSN: 0921-8971; 1573-5176
• DOI: 10.1007/s10811-024-03402-y

Heat shock transcription factors (HSFs) play a pivotal role in the high-temperature response and are found in all organisms. Terrestrial plants in particularly possess a greater number of HSF genes, suggesting their necessity for adaptation to severe dry and extreme temperature environments. Pyropia yezoensis inhabit intertidal zones subject to periodic desiccation and extreme temperature changes. Despite this, HSF genes have not yet been reported in red algae. In this study, we identify an HSF gene, PyHSF, from the marine red alga P. yezoensis . PyHSF has a DNA binding domain, oligomerization domain, and motifs that are well-conserved in the HSFA family of angiosperms. Phylogenic analyses showed that HSFs from red algae were grouped into a distinctive clade separate from those of green plants. PyHSF is located in the nucleus. When the PyHSF gene was overexpressed in the single-cell green alga Chlamydomonas , the transcription levels of heat response genes including heat shock proteins increased under normal growth conditions without heat stress, demonstrating that PyHSF acts as a transcriptional activator of these heat response genes. Transgenic Chlamydomonas cells overexpressing PyHSF showed a higher growth rate compared to wild-type cells under heat-stress conditions. PyHSF responds to high temperatures and shows different expression patterns depending on the life cycle stage of P. yezoensis . These results suggest that PyHSF has distinctive sequences those of green plants and plays an important role in regulating the growth and life cycle of P. yezoensis , which are highly affected by temperature changes.