2013年9月3日 · Our findings support OST1 as a critical limiting component in ABA regulation of stomatal apertures, ion channels and NADPH oxidases in Arabidopsis guard cells.

Using infrared thermography, we isolated two allelic Arabidopsis mutants (ost1-1 and ost1-2) impaired in the ability to limit their transpiration upon drought. These recessive ost1 mutations disrupted ABA induction of stomatal closure as well as …

2022年10月25日 · SnRK2.6, also known as Open Stomata 1 (OST1), is a serine/threonine protein kinase that plays critical roles in linking ABA receptor complexes and downstream components such as transcription factors and anion channels to regulate stress response.

2015年2月9日 · Here we report that OST1 (OPEN STOMATA 1), a well-known Ser/Thr protein kinase in ABA signaling, acts upstream of CBF s to positively regulate freezing tolerance. The ost1 mutants show freezing hypersensitivity, whereas transgenic plants overexpressing OST1 exhibit enhanced freezing tolerance. The OST1 kinase is activated by cold stress.

2019年11月4日 · Here, we show that the desensitization of the ABA signal is achieved by the regulation of OST1 (SnRK2.6) protein stability via the E3-ubiquitin ligase HOS15. Upon ABA signal, HOS15-induced degradation of OST1 is inhibited …

2022年10月19日 · 该研究通过细胞生物学、生物化学和分子遗传学等手段发现OST1介导的微管解聚是ABA诱导气孔关闭所必需的生理学过程。进一步通过互作筛选发现OST1与微管结合蛋白SPR1互作, 并且在第6位的丝氨酸磷酸化SPR1。

2018年9月19日 · The hormone abscisic acid (ABA) regulates both processes. In ABA mediated guard cell signaling the protein kinase OPEN STOMATA1 (OST1) has a central role, as stomatal closure in the ost1 mutant is impaired in response to ABA and to different environmental stimuli.

2011年11月18日 · The crystallographic structure of OST1 shows that ABA-independent regulation motif stabilizes the conformation of the kinase catalytically essential α C helix, and it provides the basis of the ABA-independent regulation mechanism for the SnRK2 family of protein kinases.

The OST1 gene was isolated and shown to encode an ABA-activated protein kinase related to the V. faba AAPK. We investigated the place of OST1 in the guard cell ABA signaling network. Our results suggest that OST1 acts in the interval between ABA perception and the production of reactive oxygen species (ROS).

Under drought stress, the stress hormone ABA addresses the SnR kinase OST1 via its cytosolic receptor and the protein phosphatase ABI1. Upon activation, OST1 phosphorylates the guard cell S–type anion channel SLAC1. Arabidopsis ABI1 and OST1 loss-of-function mutants are characterized by an extreme wilting 'open stomata′ phenotype.