Proteomic analysis and qRT-PCR verification of Arthrospira platensis strain YZ under dark stress

Abstract

Zhao X., Wang X., Zhou J., Chen B., Zeng A., Bao Q. and Wang H. 2013. Proteomic analysis and qRT-PCR verification of Arthrospira platensis strain YZ under dark stress. Phycologia 52: 538–549. DOI: 10.2216/13-167.1

Arthrospira platensis is an ideal organism for a proteome study under conditions of environmental stress. Herein, we report the differential expression of proteins in A. platensis strain YZ responding to 48 h of continuous dark or light conditions by two-dimensional gel electrophoresis and peptide mass fingerprinting techniques. There were 102 proteins retrieved with significant differential expression between light and dark incubation, among which 96 protein spots were found with high homology to Arthrospira genus (67 proteins in A. platensis strain Paraca and 29 in A. maxima strain CS-328). The other six proteins belonged to other microorganisms. Using a clusters of orthologous groups database, we classified the 102 differentially expressed positive proteins into 19 types based on their function and localized them in their respective KEGG metabolic pathways. The proteins were involved in 47 metabolic pathways, such as photosynthesis, glycolysis/gluconeogenesis pathway, oxidative phosphorylation, and amino acid and fatty acid synthesis. These results implied that the proteins performed predictable roles in rendering A. platensis strain YZ resistant against dark stress. Additionally, we determined the transcriptional level of 26 genes in response to dark stress in vivo by quantitative reverse-transcription polymerase chain reaction, and we found that the expression of six differential proteins, representing 23.08% of the total target genes, was consistent between transcriptional and translational levels. The remaining 20 genes showed inconsistent protein expression compared with the transcriptional level, which accounted for 76.92% of the total target genes.

Key Words::

• 2D-PAGE
• Arthrospira platensis
• Dark stress
• MALDI-TOF
• MS

ACKNOWLEDGEMENTS

This work was supported by the National Natural Science Foundation of China (Grant No. 31071115, 31270548, http://www.nsfc.gov.cn/Portal0/default152.htm); and the Natural Science Foundation of Zhejiang Province, China (Grant No. Y3110050, http://www.zjnsf.gov.cn/), and the Key Project of Zhejiang Environmental Protection Department, China (2012B014) and Initial Foundation of Wenzhou Medical University (QTJ13006).

SUPPLEMENTARY DATA

Supplementary data associated with this article can be found online at http://dx.doi.org/10.2216/13-167.1.s1.