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 vitamin D receptor (VDR) plays a critical role in the regulation of mineral and bone homeostasis. Upon binding of 1α,25-dihydroxyvitamin D<sub>3</sub> to the VDR, the activation function 2 (AF2) domain repositions and recruits coactivators for the assembly of the transcriptional machinery required for gene transcription. In contrast to coactivator-induced transcriptional activation, the functional effects of coactivator-independent VDR signaling remain unclear. In humans, mutations in the AF2 domain are associated with hereditary vitamin D-resistant rickets, a genetic disorder characterized by impaired bone mineralization and growth. In the present study, we used mice with a systemic or conditional deletion of the VDR-AF2 domain (Vdr<sup>ΔAF2</sup>) to study coactivator-independent VDR signaling. We confirm that ligand-induced transcriptional activation was disabled because the mutant VDR<sup>ΔAF2</sup> protein was unable to interact with coactivators. Systemic Vdr<sup>ΔAF2</sup> mice developed short, undermineralized bones with dysmorphic growth plates, a bone phenotype that was more pronounced than that of systemic Vdr knockout (Vdr<sup>-/-</sup>) mice. Interestingly, a rescue diet that is high in calcium, phosphate, and lactose, normalized this phenotype in Vdr<sup>-/-</sup>, but not in Vdr<sup>ΔAF2</sup> mice. However, osteoblast- and osteoclast-specific Vdr<sup>ΔAF2</sup> mice did not recapitulate this bone phenotype indicating coactivator-independent VDR effects are more important in other organs. In addition, RNA-sequencing analysis of duodenum and kidney revealed a decreased expression of VDR target genes in systemic Vdr<sup>ΔAF2</sup> mice, which was not observed in Vdr<sup>-/-</sup> mice. These genes could provide new insights in the compensatory (re)absorption of minerals that are crucial for bone homeostasis. In summary, coactivator-independent VDR effects contribute to mineral and bone homeostasis.
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.