Analysis of MaACS2, a stress-inducible ACC Synthase Gene in Musa acuminata AAA Group Cultivar Pisang Ambon

Resnanti Utami Handayani & Fenny M. Dwivany*

School of Life Sciences and Technology, Institut Teknologi Bandung
Jalan Ganesha No. 10 Bandung 40132 Indonesia
E-mail: fenny@sith.itb.ac.id

Abstract. Ethylene  has  an important function in plant growth and development. Ethylene  production  generally  increases  in  response  to  pathogen  attacks  and other  environmental  stress  conditions.  The  synthesis  of  this phytohormone  is regulated  by  two  enzymes,  ACC  synthase  (ACS)  and  ACC  oxidase  (ACO).  ACC synthase is encoded by a multigene  that  regulates  the  production  of ACC, after  which  this  precursor  is  converted  into  ethylene  by  ACO.  Pisang  Ambon (Musa  sp. AAA group), a banana cultivar originating from Indonesia, has nine ACS genes (MaACS  1-9) and one ACO gene (MaACO).  One  of  the  banana  ACS genes,  MaACS2,  is  stress-inducible.  In  this  research,  we  have  investigated  the expression  profile  of  MaACS2  in  the  roots  and  leaf  tissues  of  infected  tissue culture  plants.  Quantification  of  gene  expression  was analyzed using Real-Time PCR (qPCR) using  Ma18srRNA  and  MaGAPDH  as reference genes.  The results showed  nine-to  ten  fold  higher  MaACS2  expression  levels in  the  infected  roots tissues  compared to  the  uninfected roots  tissues. However,  MaACS2 expression in the leaves was only detected in infected tissue. 

Keywords: banana; environmental stress;ethylene; MaACS2; Real-Time PCR (qPCR).