인문학
사회과학
자연과학
공학
의약학
농수해양학
예술체육학
복합학
지원사업
학술연구/단체지원/교육 등 연구자 활동을 지속하도록 DBpia가 지원하고 있어요.
커뮤니티
연구자들이 자신의 연구와 전문성을 널리 알리고, 새로운 협력의 기회를 만들 수 있는 네트워킹 공간이에요.
초록·키워드
The general stress response (GSR) protects bacteria from a wide range of stressors. In Alphaproteobacteria, GSR activation is coordinated by HWE/HisKA2 family histidine kinases (HKs), which can exhibit noncanonical structure and function. For example, while most light-oxygen-voltage sensor-containing HKs are light-activated dimers, the Rubellimicrobium thermophilum RT-HK has inverted "dark on, light off" signaling logic with a tunable monomer/dimer equilibrium. Here, we further investigate these atypical behaviors of RT-HK and characterize its downstream signaling network. Using hydrogen-deuterium exchange mass spectrometry, we find that RT-HK uses a signal transduction mechanism similar to light-activated systems, despite its inverted logic. Mutagenesis reveals that RT-HK autophosphorylates in trans, with changes to the Jα helix linking sensor and kinase domains affecting autophosphorylation levels. Exploring downstream effects of RT-HK, we identified two GSR genetic regions, each encoding a copy of the central regulator PhyR. In vitro measurements of phosphotransfer from RT-HK to the two putative PhyRs revealed that RT-HK signals only to one and does so at an increased intensity in the dark, consistent with its reversed logic. X-ray crystal structures of both PhyRs revealed a substantial shift within the receiver domain of one, suggesting a basis for RT-HK specificity. We probed further down the pathway using nuclear magnetic resonance to determine that the single NepR homolog interacts with both unphosphorylated PhyRs, and this interaction is decoupled from activation in one PhyR. This work expands our understanding of HWE/HisKA2 family signal transduction, revealing marked variations from signaling mechanisms previously identified in other GSR networks.
인공지능 문자 인식 모델을 통해 추출된 텍스트로, 일부 오타나 오류가 포함될 수 있으나 지속적으로 개선 중입니다.
오류를 발견하셨다면 해당 부분을 드래그한 후 ' 를 통해 신고해주세요.
오류를 발견하셨다면 해당 부분을 드래그한 후 ' 를 통해 신고해주세요.