Cloning and expression analysis of GDP-mannose-3′,5′-epimerase (ZjGME) from Ziziphus jujuba Mill.

GDP-D-mannose-3′,5′-epimerase (GME, EC 5.1.3.18), which converts GDP-D- mannose into GDP-L-galactose, can contribute to the biosynthesis of L-ascorbic acid (AsA) in higher plants.
The fruits of Chinese jujube (Ziziphus jujuba Mill.) contain high levels of Vitamin C (higher than in most citrus fruits like the orange). In the present work, we first isolated the GME gene from Chinese jujube (ZjGME) by using homology cloning method.
It contains a 1131-bp open reading frame (ORF) and encodes a 376-amino acid protein, with an estimated molecular mass of 42.4 kDa and a theoretical pI of 5.83. ZjGME shared high similarity with those from other species, and showed the highest amino acid identity of 96% to Malpighia glabra and Prunus mume. The expression pattern of ZjGME of Z. jujuba Mill. ‘Junzao’ was monitored during fruit ripening by real-time quantitative PCR assay.
The results showed that the expression of ZjGME was relatively lower in the fruits at pre-white ripening stage than at the other stages.

XXIX International Horticultural Congress on Horticulture: Sustaining Lives, Livelihoods and Landscapes (IHC2014): III International Jujube Symposium

Y.Y. Chen, J.D. Bua, Z.H. Zhao, J. Zhao, M.J. Liu

Chinese jujube, ZjGME, cloning, expression analysis

https://doi.org/10.17660/ActaHortic.2016.1116.8