PHOTOSYNTHETICA

Photosynthetica 2019, 57(3):866-874 | DOI: 10.32615/ps.2019.078

Proteomic analysis of chloroplasts from chlorophyll-deficient melon mutant

C.M. ZHAO^1,2, J.Z. CUI³, X.G. LI¹, B.J. CHEN², R.R. JIN², Z.Y. YU¹

¹ Horticulture College, Northeast Agricultural University, No. 59 Mucai Street, Heilongjiang Province, 150030 Harbin, China

² Harbin Academy of Agricultural Science, Harbin, China

³ Life Science and Technology Institute, Harbin Normal University, Harbin, China

We aimed to understand the molecular-level changes occurring in the photosynthetic metabolic network in mutant chloro-plasts. We performed comparative liquid chromatography-mass spectrometry protein profiling of wild-type (WT) and chlorophyll-deficient melon (Cucumis melo L.) mutants. We identified 390 differentially expressed proteins and 81 shared proteins varied significantly in abundance, of which 76 were upregulated and 5 were downregulated. Differentially expressed proteins were involved in the following biological processes: binding, catalytic, structural, transporter, and antioxidant activities. The mutant had 6.08-fold higher expression of glutamate-1-semialdehyde 2,1-aminomutase (GSAM), an enzyme that synthesizes the chlorophyll precursor, 5-aminolevulinic acid, and a 5.02-fold higher expression of pyridoxal biosynthesis protein, a GSAM coenzyme. An RNA recognition motif-containing protein (RRM) decreased in expression by 5.22-fold. This suggests that GSAM and RRM are particularly relevant to chlorophyll deficiency.

Additional key words: label-free protein quantification; photosynthetic pathways; proteome analysis; qRT-PCR.

Received: May 25, 2018; Accepted: November 28, 2018; Prepublished online: July 12, 2019; Published: July 23, 2019  Show citation