COBRE: UNV MED SCH: P2: CAM KINASE II IN SMOOTH MUSCLE PLASTICITY

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。胃肠平滑肌适应不断变化的条件下的收缩活动。机械可塑性，如肥大，通过重组收缩束来改变平滑肌肉的功能能力，以应对不断变化的需求。胞浆钙振荡的幅度和频率编码了转化为生理反应的信息。CaM激酶II具有钙振荡分子解码器所需的结构、催化和调节特性。眼底和结肠平滑肌表现出明显的钙振荡，表达具有组织特异性酶特性的CaM激酶II全酶。我们将利用原位杂交、激酶分析、Western blotting和比率钙成像技术来研究CaM激酶II如何对胞浆中的钙瞬变作出反应，以了解它是如何调节平滑肌收缩活动的。先天性或获得性缺陷引起的消化道梗阻引起的胃肠道平滑肌肥大与导致几种运动障碍的病理有关。细胞体积增加的部分原因是在血清反应因子的控制下，收缩蛋白的转录和表达增加。血清反应因子是由CaM激酶II磷酸化激活的。眼底和结肠平滑肌表达含有核定位信号的CaM激酶II剪接变异体。细胞分级、Western blotting、激酶分析、Q-PCR、磷酸肽图谱和表达蛋白质组学将被用来阐明CaM激酶II在血清反应因子激活收缩蛋白基因转录中的作用。胃肠道平滑肌肥大在正常生理和疾病中具有重要意义。本项目将探索CaM激酶II在正常激动剂刺激的和异常肥大的胃肠平滑肌中的调节和生理作用。测定胃肠平滑肌CaM-KⅡ的酶特性，研究CaM-K-II对胃肠平滑肌收缩的调节作用，将为开发更好的治疗胃肠道动力障碍的肌源性成分提供更好的治疗方法。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Gastrointestinal smooth muscles adapt contractile activities in response to continuously changing conditions. Mechanical plasticity, such as hypertrophy, alters the functional capacity of smooth muscles in response to changing demands by reorganizing contractile bundles. The amplitude and frequency of cytosolic Ca 2+ oscillations encodes information that is translated into physiological responses. CaM kinase II has the structural, catalytic, and regulatory properties required of a molecular decoder of Ca 2+ oscillations. Fundus and colon smooth muscles, which exhibit distinct Ca 2¿ oscillations, express CaM kinase II holoenzymes with tissue-specific enzymatic properties. In situ hybridization, kinase assays, Western blotting, and ratiometric Ca 2¿ imaging will be used to investigate how CaM kinase II responds to cytosolic Ca 2¿ transients in order to understand how it modulates smooth muscle contractile activity. Hypertrophy of gastrointestinal smooth muscles due to obstructions of the digestive tract resulting from congenital or acquired defects is associated with pathologies that lead to several motility disorders. Part of the cell volume increase results from elevated transcription and expression of contractile proteins under the control of serum response factor. Serum response factor is activated by CaM kinase II phosphorylation. Fundus and colon smooth muscles express CaM kinase II splice variants containing a nuclear localization signal. Cellular fractionation, Western blotting, kinase assays, Q-PCR, phosphopeptide mapping, and expression proteomics will be used to elucidate the role of CaM kinase II in the activation of contractile protein gene transcription by serum response factor. Gastrointestinal smooth muscle hypertrophy is important in normal physiology and disease. This project will explore the regulation and physiological roles of CaM kinase II in normal agonist-stimulated, and abnormal hypertrophied gastrointestinal smooth muscles. Determining the enzymatic characteristics of gastrointestinal smooth muscle CaM kinase II and investigating the modulation of gastrointestinal smooth muscle contraction by CaM kinase II will provide additional information for developing better therapeutics aimed at treating the myogenic component of the altered motility patterns that underlie digestive tract motility disorders.