COMPARATIVE PROTEOMIC STUDY OF LETTUCE LEAF USING MULTI-DIMENSIONAL PROTEIN IDENTIFICATION TECHNOLOGY IN RESPONSE TO LIGHT QUALITY IN PLANT FACTORY

Plant factory offers a logical solution for sustainable food production. However, it provokes high energy and cost due to the use of artificial lighting. In this regard light quality strongly impairs growth and quality of plants due to inhibition of thylakoid multiprotein complex and photosynthetic metabolism under lighting environment. The molecular mechanism behind this phenomenon is still unclear. The objective of this research was to examine first comparative quantitative proteomic analysis of lettuce under light quality in the closed biological production system. We investigated response of lettuce proteome under three light treatments (R:B ratio of 1.2 and 2.2 provided by LEDs, and R:B ratio of 1.8 provided by the fluorescent lamp). The rapid identification and sensitive detection in protein expression in response to light quality were measured by mass spectrometry and bioinformatics followed by Mascot database used in this study. Our results demonstrated that light quality had significant effect on altering the proteomic level and expression pattern in lettuce leaves, in addition light quality had marked striking effect on functional, molecular and biological level among light treatments. The study successfully identified seventy-one proteins for lettuce plants treated with fluorescent lamps, fifty and forty-one for LEDs, respectively, which were involved in energy metabolism and regulation of morphogenesis. The results observed dramatically altered molecular mechanism of key enzymes in thylakoid complex proteins and photosynthetic metabolism among light treatments due to effect of spectral light quality difference. Importantly, the lettuce plants have lower expression of proteins diagnostic for LEDs light. In this regard our data will provide foundation for future detail study to unlock the advantages of this next generation lighting technology to strengthen the connection between light quality and multi complex protein (CB23_HORVU) of LHC family in highly energy-efficient horticulture.