Regulation of Heat Stress in Physcomitrium (Physcomitrella) patens Provides Novel Insight into the Functions of Plant RNase H1s

Abstract

RNase H1s are associated with growth and development in both plants and animals, while the roles of RNase H1s in bryophytes have been rarely reported. Our previous data found that PpRNH1A, a member of the RNase H1 family, could regulate the development of Physcomitrium (Physcomitrella) patens by regulating the auxin. In this study, we further investigated the biological functions of PpRNH1A and found PpRNH1A may participate in response to heat stress by affecting the numbers and the mobilization of lipid droplets and regulating the expression of heat-related genes. The expression level of PpRNH1A was induced by heat stress (HS), and we found that the PpRNH1A overexpression plants (A-OE) were more sensitive to HS. At the same time, A-OE plants have a higher number of lipid droplets but with less mobility in cells. Consistent with the HS sensitivity phenotype in A-OE plants, transcriptomic analysis results indicated that PpRNH1A is involved in the regulation of expression of heat-related genes such as DNAJ and DNAJC. Taken together, these results provide novel insight into the functions of RNase H1s.

Multilevel analysis between Physcomitrium patens and Mortierellaceae endophytes explores potential long‐standing interaction among land plants and fungi

“…Reduced photosynthesis Plant Journal, (2024), 118, 304-323 Evolution of early land plant-fungal relations 309 activity has been reported as one of the first actions in the immune response to both abiotic and biotic stressors (Lu & Yao, 2018;Yang et al, 2022). Typically, during the early stages of infection photosynthetic activity is reduced and even after infection has passed transcript accumulation can remain low (Chen, Cui, et al, 2015;Hu et al, 2020;Scharte et al, 2005;Swarbrick et al, 2006;Yang et al, 2022). We also investigated highly expressed individual genes outside the gene ontology (GO) categories, whose differential expression posed interesting considerations.…”

Alternative Splicing: From Abiotic Stress Tolerance to Evolutionary Genomics

“…With global warming, heat stress has become a major limiting factor for crop yield improvement. Yang et al discovered two family members of RNase H1 in the moss Physcomitrium patens [ 4 ], a representative model for early-diverging land plants. They indicated the presence of homologues to the RNase H1 genes in chlorophytes and charophytes, suggesting an early origin for this gene family.…”