Overcoming heat shock protein inhibition at critical temperature vital for survival in <i>Solanum tuberosum</i> L. <i>in vivo</i> condition

Abstract

Heat stress proteins (HSPs) and related cognates are candidates mediating and preventing cellular damage  from heat-stress, but their expression can be inhibited midway. The time-based occurrence pattern for heat mediated inhibition underlying HSPs expression at 41.5°C and revival subsequent stress was studied in vivo for four Solanum tuberosum L. cultivars viz. Kufri Pukhraj, Kufri Jyoti, Kufri Chandramukhi and Kufri Ashoka. Our  results show that the inhibition process is a functional variance of time and genetic variability characterized by differential down-regulation of housekeeping proteins (HKPs) of about 55.7 and 43.5 KD in some cultivars and  complete inhibition of a prominent 19.9 KD HKP in Kufri Jyoti at all stressed time. Furthermore, the results  strongly suggest HSPs inhibition process bridges the gap between normal proteome and spur expression  maxima for stress proteome and may last for about 1 h for cultivars that effectively eludes the process  upgrading their thermotolerance in vivo.

Key words: Solanum tuberosum L., heat-mediated inhibition, heat shock proteins, housekeeping proteins.