Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2013 Jul;18(4):427-37.
doi: 10.1007/s12192-012-0395-6. Epub 2012 Dec 21.

Functional analysis of Hsp70 superfamily proteins of rice (Oryza sativa)

Neelam K Sarkar  1 , Preeti Kundnani, Anil Grover
Affiliations

Functional analysis of Hsp70 superfamily proteins of rice (Oryza sativa)

Neelam K Sarkar et al. Cell Stress Chaperones. 2013 Jul.

Abstract

Heat stress results in misfolding and aggregation of cellular proteins. Heat shock proteins (Hsp) enable the cells to maintain proper folding of proteins, both in unstressed as well as stressed conditions. Hsp70 genes encode for a group of highly conserved chaperone proteins across the living systems encompassing bacteria, plants, and animals. In the cellular chaperone network, Hsp70 family proteins interconnect other chaperones and play a dominant role in various cell processes. To assess the functionality of rice Hsp70 genes, rice genome database was analyzed. Rice genome contains 32 Hsp70 genes. Rice Hsp70 superfamily genes are represented by 24 Hsp70 family and 8 Hsp110 family members. Promoter and transcript expression analysis divulges that Hsp70 superfamily genes plays important role in heat stress. Ssc1 (mitochondrial Hsp70 protein in yeast) deleted yeast show compromised growth at 37 °C. Three mitochondrial rice Hsp70 sequences (i.e., mtHsp70-1, mtHsp70-2, and mtHsp70-3) complemented the Ssc1 mutation of yeast to differential extents. The information presented in this study provides detailed understanding of the Hsp70 protein family of rice, the crop species that is the major food for the world population.

PubMed Disclaimer

Figures

Fig. 1
Fig. 1
Phylogenetic analysis of Hsp70 superfamily of rice. a Amino acid sequences of rice Hsp70 superfamily genes aligned in clustalX (2.0) were used for generating NJ tree with bootstrap. Phylogenetic tree was visualized in Treeview 1.6.6. The numbers for the interior nodes indicate the bootstrap values for 1,000 replications. The scale at the bottom is the number of amino acid substitutions per site. Segmental duplicated pairs are marked with similar color symbols. b Exon–intron arrangement of Hsp70 superfamily genes. The exons and introns are represented by box and lines, respectively. The order of genes in (b) match with the order shown in (a)
Fig. 2
Fig. 2
Analysis of conserved motifs present in Hsp70 family proteins. a Domain architecture of Hsp70 and Hsp110 proteins. b Analysis of conserved motifs present in Hsp70 family proteins. Motifs were identified by MEME software using complete amino acid sequences of Hsp70 proteins. The protein sequences are arranged in the order as shown in tree in Fig. 1. Color code of the motifs is depicted on right side. c Multilevel consensus sequences of MEME-derived motifs. Single letters in the motif match that letter; groups of letters in square brackets match any of the letters in the group
Fig. 3
Fig. 3
Expression analysis of Hsp70 genes of rice. a Semi-quantitative RT-PCR of selective Hsp70 genes under stress conditions. Rice seedlings were given stress under different conditions as mentioned: HS1 heat shock at 42 °C for 10 min, HS2 heat shock at 42 °C for 1 h, ABA 100 μM abscisic acid for 3 h, CS cold stress at 6 °C for 6 h, SS salt stress in 150 mM NaCl for 6 h, C control maintained at 26 °C. b Microarray based expression profiles during heat stress and recovery conditions as described (Sarkar et al. 2009). HS_10 heat stress at 42 °C for 10 min, HS_60 heat stress at 42 °C for 1 h, HS_Rec 30 min recovery after heat stress at 42 °C for 1 h. c Heat map showing in silico expression data retrieved from Genevestigator (www.genevestigator.com/)
Fig. 4
Fig. 4
Expression of rice mitochondrial Hsp70 proteins partially complement yeast Hsp70 mutant. a The mitochondrial Hsp70 genes of rice were cloned under the GPD promoter in p426 vector and transformed in yeast mutant cells (ssc1-3/PK83: MATα ssc1-3 ade2 lys2 ura3 trp1) having mutation in mitochondrial Hsp70 gene (Ssc1). The cells were grown to log phase, growth was normalized to 0.2 OD, and tenfold serial dilutions of wild type, yeast mutant cells transformed with vector and transformed with rice Hsp70 were spotted on selection medium and plates were incubated at 26 and 37 °C. UD is normalized OD600 0.2. Tree depicts rice and yeast mitochondrial Hsp70 genes. b Subset of the phylogenetic tree showing relationship amongst rice and yeast proteins analyzed in this assay
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Acebron SP, Martin I, del Castillo U, Moro F, Muga A. DnaK-mediated association of ClpB to protein aggregates. A bichaperone network at the aggregate surface. FEBS Lett. 2009;583:2991–2996. doi: 10.1016/j.febslet.2009.08.020. - DOI - PubMed
    1. Bailey TL, Williams N, Misleh C, Li WW. MEME: discovering and analyzing DNA and protein sequence motifs. Nucleic Acids Res. 2006;34:W369–W373. doi: 10.1093/nar/gkl198. - DOI - PMC - PubMed
    1. Cannon SB, Mitra A, Baumgarten A, Young ND, May G. The roles of segmental and tandem gene duplication in the evolution of large gene families in Arabidopsis thaliana. BMC Plant Biol. 2004;4:10. doi: 10.1186/1471-2229-4-10. - DOI - PMC - PubMed
    1. Cho EK, Choi YJ. A nuclear-localized HSP70 confers thermoprotective activity and drought-stress tolerance on plants. Biotechnol Lett. 2009;31:597–606. doi: 10.1007/s10529-008-9880-5. - DOI - PubMed
    1. DeRocher A, Vierling E. Cytoplasmic HSP70 homologues of pea: differential expression in vegetative and embryonic organs. Plant Mol Biol. 1995;27:441–456. doi: 10.1007/BF00019312. - DOI - PubMed

Publication types

Substances