biologia plantarum

Biologia plantarum 60:459-468, 2016 | DOI: 10.1007/s10535-016-0619-1

Molecular cloning and expression of four phenylalanine ammonia lyase genes from banana interacting with Fusarium oxysporum

Z. Wang¹, J.-Y. Li², C.-H. Jia¹, J.-P. Li¹, B.-Y. Xu^1,*, Z.-Q. Jin^1,2

¹ Key Laboratory of Tropical Crop Biotechnology, Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Hainan, P.R. China

² Haikou Experimental Station, Chinese Academy of Tropical Agricultural Sciences, Hainan, P.R. China

Phenylalanine ammonia lyase (PAL) is the first enzyme in the phenylpropanoid pathway. In this study, we describe the molecular characteristics of four PAL genes (MaPAL1, MaPAL2, MaPAL3, and MaPAL4) cloned from banana (Musa acuminata L. AAA group, cv. Cavendish) using a rapid amplification of cDNA ends and real time quantitative PCR. The predicted molecular masses of corresponding PALs ranged from 70.2 to 77.3 kDa and their isoelectric points were acidic. At the amino acid level, they shared a high sequence similarity with PALs in the banana DH-Pahang (AA group) genome. Phylogenetic analysis shows that the deduced amino acid sequences of MaPALs had also a high similarity with PALs of other plant species. Expression analysis by semi-quantitative reverse transcriptase PCR reveals that these genes were differentially expressed in various tissues. Enzyme activity of PAL and expression of MaPALs in bananas were induced after infection with Fusarium oxysporum f. sp cubense Tropical Race 4. Our findings suggest that MaPALs play important roles in banana resistance to F. oxysporum.

Keywords: disease resistance; gene expression; Musa acuminata; real time qPCR

Subjects: gene expression; phenylalanineammonia lyase; amino acid sequence; phylogenetic tree; fungal infection; banana

Received: January 21, 2015; Revised: October 21, 2015; Accepted: November 3, 2015; Published: September 1, 2016  Show citation