Abstract
The mitogen-activated protein kinase (MAPK) cascades play important roles in various signaling transduction networks of biotic and abiotic stress responses. However, MAPK signaling pathways in cold-active yeast Rhodotorula mucilaginosa have not been reported comprehensively. In the present study, MAPK gene ( RmMAPK ) was first cloned and characterized from Antarctic sea ice yeast R. mucilaginosa AN5. The full length of the RmMAPK gene is 1086 bp and encodes a 361 amino acids protein with a predicted molecular mass of 40.9 kDa and a pI of 5.25. The RmMAPK contains 11 MAPK conserved subdomains and the phosphorylation motif TGY located in the activation loop of the kinase. Quantitative real-time PCR assay revealed that the expression of RmMAPK up-regulated rapidly and significantly when yeast cells were subjected to low temperature (4 °C), high salinity (120‰ NaCl) and heavy metal (2 mmol/L CuCl 2 ), which suggested that the RmMAPK might act as a key function in response to extreme stresses, such as low temperature, high salinity and heavy metal.
The Tomato Mitogen-Activated Protein Kinase SlMPK1 Is as a Negative Regulator of the High-Temperature Stress Response