Genome-wide expression profiling of aquaporin genes confer responses to abiotic and biotic stresses in Brassica rapa. Issue 1 (December 2017) - Kayum, Md.
Abstract Background Plants contain a range of aquaporin (AQP) proteins, which act as transporter of water and nutrient molecules through living membranes. AQPs also participate in water uptake through the roots and contribute to water homeostasis in leaves. Results In this study, we identified 59AQP genes in theB. rapa database and Br135K microarray dataset. Phylogenetic analysis revealed four distinct subfamilies ofAQP genes: plasma membrane intrinsic proteins (PIPs), tonoplast intrinsic proteins (TIPs), NOD26-like intrinsic proteins (NIPs) and small basic intrinsic proteins (SIPs). Microarray analysis showed that the majority of PIP subfamily genes had differential transcript abundance between twoB. rapa inbred lines Chiifu and Kenshin that differ in their susceptibility to cold. In addition, allBrPIP genes showed organ-specific expression. Out of 22 genes, 12, 7 and 17 were up-regulated in response to cold, drought and salt stresses, respectively. In addition, 18BrPIP genes were up-regulated under ABA treatment and 4BrPIP genes were up-regulated uponF. oxysporum f. sp.conglutinans infection. Moreover, allBrPIP genes showed down-regulation under waterlogging stress, reflecting likely the inactivation of AQPs controlling symplastic water movement. Conclusions This study provides a comprehensive analysis of AQPs inB. rapa and details the expression of 22 members of theBrPIP subfamily. These results provide insight into stress-related biological functions of eachPIP gene of the AQP family, which will promoteB. rapa breeding programs.