Overexpression of the Small Heat Shock Protein, PtsHSP19.3 from Marine Red Algae, Pyropia tenera (Bangiales, Rhodophyta) Enhances Abiotic Stress Tolerance in Chlamydomonas

Abstract

This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.Abstract Water temperature is one of the major factors that impacts the growth and life cycle of Pyropia tenera, one of the most valuable and cultivated marine red algae belonging to Bangiales (Rhodophytes). We analyzed transcriptome from gametophyte of P. tenera under normal and high temperature conditions, and identified four small heat shock proteins (sHSPs). They have no significant amino acid sequence homology with known proteins in public databases except PhsHSP22 from Pyropia haitanensis. PtsHSP19.3 gene responded to high temperature but slightly or not to desiccation, freezing or high salt condition. When the PtsHSP19.3 gene was overexpressed in Chlamydomonas reinhardtii, transformed Chlamydomonas lines revealed much higher growth rate than that of control cells under heat stress condition. Transformed cells also grew well in those of the control cell onto the medium containing high salt or H 2 O 2 . When the PtsHSP19.3 was fused to GFP and introduced into tobacco protoplast, fluorescence was detected at several spots. Results indicate that PtsHSP19.3 may form super-molecular assembles and be involved in tolerance to heat stress.

Molecular mechanism underlying Pyropia haitanensis PhHsp22-mediated increase in the high-temperature tolerance of Chlamydomonas reinhardtii

“…3). These results are similar to those of an earlier transgenic study (Jin et al 2017). The expression of the Pyropia tenera HSP19.3 gene inserted into the C. reinhardtii genome is reportedly upregulated soon after initiating a HT treatment and confers Fig.…”

“…The expression of the Pyropia tenera HSP19.3 gene inserted into the C. reinhardtii genome is reportedly upregulated soon after initiating a HT treatment and confers Fig. 5 Heat map of the differentially expressed genes involved in the proteasome, ubiquitin-mediated proteolysis, protein processing in the endoplasmic reticulum (ER), and citrate cycle (TCA cycle) between WT-CK (wild-type unstressed control) and HSP-CK (transgenic C. reinhardtii unstressed control) the tolerance to heat (Jin et al 2017). Our data suggest that PhHsp22 from P. haitanensis might play a significant role in resisting HT stress.…”

“…Moreover, many heterologous genes have been expressed in C. reinhardtii, including genes from microalgae (Cordero et al 2011), macroalgae (Kim et al 2011), higher plants (Siripornadulsil et al 2002), and humans (Rasala and Mayfield 2011). Specifically, Jin et al (2017) inserted the Pyropia tenera HSP19.3 gene into C. reinhardtii and confirmed that the physiological function of the encoded protein may influence HT tolerance. Accordingly, C. reinhardtii may be suitable for expressing P. haitanensis genes.…”

Characterization and expression profiles of small heat shock proteins in the marine red alga Pyropia yezoensis

“…In addition, the PysHSPs contained a BI/V-x-I/ V^motif, highly conserved across many sHSPs and affects the oligomerization (Pasta et al 2004). These two conserved motifs have also been found in sHSPs from the red algae P. tenera (Jin et al 2017) and C. merolae (Kobayashi et al 2014). Phylogenetic analysis revealed that All PysHSPs were classified with the clusters of sHSPs from the red algae that were distinct from those of land plants and green algae (Fig.…”

“…Transcriptome analysis has revealed the upregulation of HSPs, including sHSPs, under high-temperature conditions in Pyropia species (Park et al 2012;Sun et al 2015), and it has also been shown that the overexpression of sHSPs from Pyropia tenera enhances heat stress tolerance in C. reinhardtii (Jin et al 2017). Furthermore, proteome analysis has shown that HSP22 is upregulated under desiccation stress in Pyropia orbicularis (López-Cristoffanini et al 2015).…”