Abstract:

The objective of this work was to investigate changes in proteins during the color-changing period of litchi aril
(Litchi chinensis Sonn.) on the process of quality formation. The comparison of the protein patterns of the litchi cultivars
“Wuye” and “Lanzhu” using gel-based proteomics technique showed that 37 protein spots were more than 2 times
differentially expressed in both cultivars, of which 32 were successfully identified by MALDI-TOF/TOF-MS. The identified
proteins were divided into categories related to carbohydrate and energy metabolism (21.9%), stress resistance (9.4%),
protein metabolism (15.6%), cell structure formation (12.5%), secondary metabolism (12.5%), developmental regulation
(12.5%), and unknown function (15.6%). Compared to the “Lanzhu” cultivar, the proteins related to glycolytic pathway and
energy metabolism were decreased in “Wuye” litchi fruits, implying that slow sugar degradation in the litchi cultivar “Wuye”
was beneficial to the accumulation of sugar and formation of high sugar quality. Besides, the increase of proteins associated with
cell structure formation and stress resistance contributed to form the quality of dense texture and good shelf stablility in the litchi
cultivar “Wuye” when compared to “Lanzhu”. Our findings provide a scientific basis for improving the quality of litchi fruits.

Key words: Litchi chinensis Sonn., aril, differentially expressed proteins, quality