Sanjay Kapoor

Friday seminar by Ms. Shaloo Meena


PK Lab/ Friday June 7, 2019/ 3.30 pm/ Pollen development under heat stress
Category: Research
Posted by: bedineel

 

Pollen development under heat stress

 

Shaloo Meena

Reproductive development in sexual plants is substantially more sensitive to high temperature stress than vegetative development, but the basis of this phenomenon is poorly understood. High temperature exposure either during early pollen development or during the progamic phase of pollen development will negatively impact pollen performance and reproductive output; both phase of pollen development are considered exceptionally sensitive to moderate heat stress. High temperature has been shown to affect the quantity, chemical composition, metabolism, morphology and viability of pollen. Therefore, to overcome the stress, developing pollen has the capacity for acclimation and acquired thermotolerance. There are experimental evidences for a role of both HSR and UPR in heat acclimation of anthers and pollen. HsfA2 is an important coactivator of HsfA1a during HSR and it suppression reduces the viability and germination rate of pollen that received the stress during the stages of meiosis and microspore formation. Therefore, HsfA2 is an important factor for the priming process that sustains pollen thermotolerance during microsporogenesis. IRE1 is a dual protein kinase/ribonuclease involved in the splicing of bZIP60 mRNA, and through complementation analysis of various mutant forms of IRE1b it was demonstrated that the ribonuclease activity of IRE1 was required for protecting male fertility from high temperature. Therefore, IRE1 a major component of the UPR, plays an important role in protecting pollen development from high temperature.

  1. Deng, Y., Srivastava, R., Quilichini, T. D., Dong, H., Bao, Y., Horner, H. T., & Howell, S. H. (2016). IRE 1, a component of the unfolded protein response signaling pathway, protects pollen development in Arabidopsis from heat stress. The Plant Journal88(2), 193-204.
  2. Rieu, I., Twell, D., & Firon, N. (2017). Pollen development at high temperature: from acclimation to collapse. Plant physiology173(4), 1967-1976.
  3. Fragkostefanakis, S., Mesihovic, A., Simm, S., Paupière, M. J., Hu, Y., Paul, P., ... & Schleiff, E. (2016). HsfA2 controls the activity of developmentally and stress-regulated heat stress protection mechanisms in tomato male reproductive tissues. Plant physiology170(4), 2461-2477.