Calcium-dependent protein kinase 32 gene maintains photosynthesis and tolerance of potato in response to salt stress

Calcium-dependent protein kinase 32 (StCDPK32) of potato is identified as a mono-molecular Ca2+-sensor/kinase-effector protein encoding by StCDPK32. This study aims to understand the mechanism of StCDPK32 involved in resisting to salinity stress. StCDPKs were examined in Solanum tuberosum L. cv. Zihuabai treated with 200 mM NaCl for 0-48 h. To investigate the ability of potato to resist salt stress, Zihuabai was cultured in NaCl-conditioned medium. To explore the effects of StCDPK32 on physiochemical activities and gas exchange, StCDPK32-upregulated and StCDPK32-downregulated potato plants were developed with Agrobacterium tumefaciens-mediated transformation method. Subcellular location of StCDPK32 protein was detected using confocal scanning laser microscopy. It was found that NaCl treatment resulted in transcription change of StCDPKs. Salinity treatment promoted StCDPK32 transcription in potato plants. StCDPK32-transgenic plants are tolerant to NaCl while StCDPK32-repressed plants are sensitive to NaCl in comparison with the untransgenic plants. StCDPK32 overexpression elevates genes expression and enzyme activities associated with salt stress. Additionally, photosynthesis is promoted by StCDPK32 overexpression under salt stress conditions. StCDPK32 protein localizes in nucleus, cytoplasm and cellular membrane. StCDPK32 positively modulates physiological properties and photosynthesis in response to salinity stress. StCDPK32 is a potential candidate gene for growth improvement under salt conditions.

Automated summary

This study aimed to understand the mechanism of StCDPK32 in resisting salinity stress in potato and found that StCDPK32 positively modulates physiological properties and photosynthesis under salt stress conditions, making it a potential candidate gene for growth improvement under salt conditions.