Open AccessTransgenic banana plants overexpressing a native plasma membrane aquaporin M usa PIP 1;2 display high tolerance levels to different abiotic stresses
Author(s) -
Sreedharan Shareena,
Shekhawat Upendra K. S.,
Ganapathi Thumballi R.
Publication year - 2013
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/pbi.12086
Subject(s) - aquaporin , abiotic component , abiotic stress , transgene , biology , microbiology and biotechnology , genetically modified crops , green fluorescent protein , proline , drought tolerance , water transport , botany , gene , biochemistry , water flow , ecology , amino acid , environmental engineering , engineering
Summary Water transport across cellular membranes is regulated by a family of water channel proteins known as aquaporins ( AQP s). As most abiotic stresses like suboptimal temperatures, drought or salinity result in cellular dehydration, it is imperative to study the cause–effect relationship between AQP s and the cellular consequences of abiotic stress stimuli. Although plant cells have a high isoform diversity of AQP s, the individual and integrated roles of individual AQP s in optimal and suboptimal physiological conditions remain unclear. Herein, we have identified a plasma membrane intrinsic protein gene ( Musa PIP 1;2) from banana and characterized it by overexpression in transgenic banana plants. Cellular localization assay performed using M usa PIP 1;2:: GFP fusion protein indicated that M usa PIP 1;2 translocated to plasma membrane in transformed banana cells. T ransgenic banana plants overexpressing M usa PIP 1;2 constitutively displayed better abiotic stress survival characteristics. The transgenic lines had lower malondialdehyde levels, elevated proline and relative water content and higher photosynthetic efficiency as compared to equivalent controls under different abiotic stress conditions. Greenhouse‐maintained hardened transgenic plants showed faster recovery towards normal growth and development after cessation of abiotic stress stimuli, thereby underlining the importance of these plants in actual environmental conditions wherein the stress stimuli is often transient but severe. Further, transgenic plants where the overexpression of M usa PIP 1;2 was made conditional by tagging it with a stress‐inducible native dehydrin promoter also showed similar stress tolerance characteristics in in vitro and in vivo assays. Plants developed in this study could potentially enable banana cultivation in areas where adverse environmental conditions hitherto preclude commercial banana cultivation.