Isolation and Expression of Catalase CAT2 Gene from Luffa cylindrical

Abstract: The RNA-seq technique was used to analyze the changes of transcriptomic occurring in the browning of fruits from Luffa cultivar ‘WL3’. A total of 58 073 unigenes were assembled from high-quality reads， and 27 301 unigenes were differentially expressed during the browning process of Luffa fruits. In this study， full length of agene sequence (i.e.， unigene0033876) annotated as catalase CAT gene was filtrated from the differentially expressed genes. The sequence analysis showed that unigene0033876 reached a length of 1 690 bp and contained a 1 479 bp open reading frame (ORF) that encoded 492 amino acids， with a predicted molecular weight of 56.94 kDa and a hypothetical isoelectric point of 7.31. It shared over 97% identity with the homologous proteins from Cucurbita moschata， Cucurbita pepo and Cucumis sativus， revealing that it was highly conservative， and the GenBank accession was KR184674. The results of qPCR (Real-time quantitative PCR) revealed that LcCAT2 exhibited a tissue specific expression， the expression level in Luffa cultivar ‘WL-3’ leaves was the highest， and minimally expressed in flowers on the contrary. The levels of LcCAT2 were different among six luffa varieties， and the expression in Luffa cylindrical was higher than that in Luffa acutangula Roxb. Furthermore， the level of LcCAT2 in ‘WL3’ was up-regulated during post-harvest storage， suggesting that LcCAT2 gene may play a regulatory role in luffa browning process. The survey aims to excavate the genes associated with Luffa browning from transcriptome sequencing results， and make contributions to breeding of the Luffa varieties and ulteriorly revealing the molecular mechanism of Luffa enzymatic browning process for the future.

CSTR: 32200.14.cjcb.2017.08.0011