AUTHOR=Mu Ying , Liu Yumei , Bai Longqiang , Li Shuzhen , He Chaoxing , Yan Yan , Yu Xianchang , Li Yansu 

TITLE=Cucumber CsBPCs Regulate the Expression of CsABI3 during Seed Germination

JOURNAL=Frontiers in Plant Science

VOLUME=8

YEAR=2017

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2017.00459

DOI=10.3389/fpls.2017.00459

ISSN=1664-462X

ABSTRACT=<p>Cucumber seeds with shallow dormancy start to germinate in fruit that are harvested late. ABSCISIC ACID INSENSITIVE3 (ABI3), a transcription factor in the abscisic acid (ABA) signaling pathway, is one of the most important regulators in the transition from late embryogenesis to germination. Our analysis found a candidate cis-regulatory motif for cucumber BASIC PENTACYSTEINE (CsBPC) in the promoter of <italic>CsABI3</italic>. Yeast one-hybrid and chromatin immunoprecipitation (ChIP) assays showed that CsBPCs bound to the promoter of <italic>CsABI3</italic>. Examination of β-glucuronidase (GUS) activity driven by the <italic>CsABI3</italic> promoter in transgenic <italic>Arabidopsis thaliana</italic> plants overexpressing <italic>CsBPCs</italic> and a <italic>Nicotiana benthamiana</italic> (tobacco) luciferase assay indicated that CsBPCs inhibited the expression of <italic>CsABI3</italic>. Transgenic plants overexpressing <italic>CsBPCs</italic> were constructed to confirm that CsBPCs participates in the control of seed germination. This study of the cucumber BPC-ABI3 pathway will help to explore and characterize the molecular mechanisms underlying seed germination and will provide necessary information for seed conservation in agriculture and forestry.</p>