|SETTER, TIM - Cornell University - New York|
Submitted to: Environmental and Experimental Botany
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/22/2015
Publication Date: 11/30/2015
Citation: Yu, L., Setter, T. 2015. Comparative transcriptomes between viviparous1 and wildtype maize developing endosperms in response to water deficit. Environmental and Experimental Botany. 123:116–124.
Interpretive Summary: Maize kernel development is particularly sensitive to water stress at the early post-pollination phase. Endosperm plays an essential role in support of embryo development. By comparing gene transcriptional profiles of developing maize endosperms between an ABA-insensitive mutant, viviparous1 and wildtype under water deficit, we identified a number of genes whose expressions were significantly affected by water deficit in developing maize endosperm. These genes play roles in regulating gene expression in maize early endosperm development in response to water deficit. Further investigation of these genes will provide an insight window to understand mechanisms by which water deficit affects maize kernel abortion caused by drought stress.
Technical Abstract: Maize kernel development is particularly sensitive to water stress at the early post-pollination phase. Endosperm plays an essential role in support of embryo development. In the present study, we compared transcriptomes of developing maize endosperms between an ABA-insensitive mutant, viviparous1 (vp1), and wild type (wt) under water deficit. A total of 121 and 164 transcripts were significantly affected by water deficit in vp1 and wt, respectively. Transcript profiles indicated that the Vp1 transcription factor contributed to regulation in response to water stress at early stages of maize endosperm development. Genes involved in transcriptional regulation and signal transduction were particularly dependent on presence of a functional Vp1 allele, as 83% the stress-affected genes in these categories were up-regulated by water stress in the wt, but only 34% were up-regulated in the mutant. This suggests that the loss of ABA sensitivity altered signaling networks in response to water deficit such that the mutant was unable to up-regulate the expression of many genes that normally play regulatory roles. Thus, the Vp1 gene plays a role in regulating gene expression in maize endosperm development in response to water deficit, and this regulation is likely modulated via ABA signaling pathway.