Differential proteomic analysis by iTRAQ reveals the growth mechanism in Pyropia yezoensis mutant

The previous study revealed that the mutant strain E thalli of Pyropia yezoensis had growth advantage compared with the initial strain NA, and transcriptome analysis revealed the relevant bioprocesses for improved growth. To investigate the growth mechanism at the protein level, this study used isobaric tags for relative and absolute quantification and liquid chromatography-mass spectrometry to analyze proteome of both strains. In total, 277 proteins were identified, among which 41 differentially expressed proteins were screened, including 22 up regulated proteins and 19 down-regulated proteins. Integrated analysis of proteome and previous transcriptome showed that the proteins related to photosynthesis, protein biosynthesis, glycolysis, and pentose phosphate pathway were enhanced in mutant strain E, which were supposed to facilitate growth of mutant strain E, and the proteins relevant to stress resistance were up-regulated, which might promote the growth of mutant strain E under abiotic stresses, while proteins related to methylation were decreased, which might enhance the expression of growth relevant genes in mutant strain E. This study revealed the growth mechanism in mutant strain E by integrated omics analysis, and also provided theoretical foundation for molecular breeding of Py. yezoensis.

Automated summary

This study analyzed the proteome changes in the mutant strain E and initial strain NA of Pyropia yezoensis, showing that the mutant strain E had enhanced proteins related to photosynthesis, protein biosynthesis, and glycolysis, promoting its growth. It also exhibited increased stress resistance, while proteins related to methylation were decreased in mutant strain E. This research provides a theoretical foundation for molecular breeding of Py. yezoensis.