AUTHOR=Khatun Muslima , Borphukan Bhabesh , Alam Iftekhar , Keya Chaman Ara , Panditi Varakumar , Khan Haseena , Huq Saaimatul , Reddy Malireddy K. , Salimullah Md. TITLE=Mitochondria-Targeted SmsHSP24.1 Overexpression Stimulates Early Seedling Vigor and Stress Tolerance by Multi-Pathway Transcriptome-Reprogramming JOURNAL=Frontiers in Plant Science VOLUME=Volume 12 - 2021 YEAR=2021 URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.741898 DOI=10.3389/fpls.2021.741898 ISSN=1664-462X ABSTRACT=Among the diverse array of heat shock proteins across the three domains of life, mitochondria-targeted small heat shock proteins (sHSPs) are evolved in plant lineage, however, they remained mysterious and understudied. Here, we report a systematic study of a novel mitochondria-targeted nuclear sHSP from eggplant (SmsHSP24.1). Differential expression of SmsHSP24.1 indicates its positive role exerted during stress conditions. E. coli-BL21cell line overexpressing the SmsHSP24.1 shows excellent thermo-tolerance ability, tolerating up to 52 ºC. Spectrometry and electron microscopy reveal a multimeric structure of the protein which acts as a molecular chaperone at high temperatures. Overexpression of SmsHSP24.1 significantly enhanced resistance against heat, drought, and salt stresses and showed rapid germination in constitutively overexpressed eggplant lines. RNA-seq analysis reveals an apparent upregulation of a set of reactive oxygen species (ROS)-scavenging enzymes of the glutathione (GHS) pathway and mitochondrial electron transport chain (ETC). Significant upregulation was also observed in auxin biosynthesis and cell-wall remodeling transcripts in overexpressed lines. qPCR, biochemical and physiological analysis further aligned with a finding of transcriptome analysis and suggest an essential role of SmsHSP24.1 under various stress responses and positive physiological influence on the growth of eggplants. This gene, therefore, has immense potential in engineering stress-resilient crop plants.