عنوان
پدید آورنده
موضوع
رده
کتابخانه
محل استقرار
شماره کتابشناسی ملی
شماره
TLpq304461542
زبان اثر
زبان متن نوشتاري يا گفتاري و مانند آن
انگلیسی
عنوان و نام پديدآور
عنوان اصلي
Ca(2+)-desensitization in smooth muscle:
نام عام مواد
[Thesis]
نام نخستين پديدآور
X. Wu
عنوان اصلي به قلم نويسنده ديگر
From cyclic nucleotides, telokin, to myosin light chain phosphatase
نام ساير پديدآوران
A. V. Sombyo
وضعیت نشر و پخش و غیره
نام ناشر، پخش کننده و غيره
University of Virginia
تاریخ نشرو بخش و غیره
1998
مشخصات ظاهری
نام خاص و کميت اثر
112
یادداشتهای مربوط به پایان نامه ها
جزئيات پايان نامه و نوع درجه آن
Ph.D.
کسي که مدرک را اعطا کرده
University of Virginia
امتياز متن
1998
یادداشتهای مربوط به خلاصه یا چکیده
متن يادداشت
Cyclic nucleotides, cAMP or cGMP, relaxes smooth muscle by lowering usd\rm\lbrack Ca\sp{2+}\rbrack\sb{in}usd and/or decrease the sensitivity of contractile elements to usd\rm Ca\sp{2+}.usd The following results suggested that enhancement of smooth muscle myosin light chain phosphatase (SMPP-1M) activity accounted for usd\rm Ca\sp{2+}usd-desensitization induced by cGMP: cGMP-dependent relaxation of smooth muscle was associated with a decrease in phosphorylation of the regulatory myosin light chain (MLC{20}); cGMP accelerated both relaxation and dephosphorylation of MLC{20} independently of myosin light chain kinase activity; cGMP did not affect thiophosphorylation of MLC{20}. Furthermore, 8-bromo-cGMP-dependent stimulation reversed G-protein-coupled inhibition of SMPP-1M activity. Incorporation of P into telokin, a smooth muscle-specific, 17-18 kDa, acidic protein, was increased by forskolin in intact and by 8-bromo-cGMP in usd\alphausd-toxin permeabilized rabbit ileum smooth muscle (ileum). Native telokin, purified from turkey gizzard, and recombinant rabbit telokin, expressed in E. coli and purified, induced dose-dependent relaxation, associated with a significant decrease in MLC{20} phosphorylation, without affecting the rate of thiophosphorylation of MLC{20} of ileum permeabilized with Triton X-100. It remains unclear whether telokin has a direct stimulatory effect on SMPP-1M. Endogenous telokin was lost from ileum during permeabilization with Triton X-100, and the time course of loss was correlated with the loss of 8-bromo-cGMP-induced Ca-desensitization. Recombinant and native telokins were phosphorylated, in vitro, by the catalytic subunit of cAMP-dependent protein kinase, cGMP-dependent protein kinase (PKG), p42/44 mitogen-activated protein kinase; the recombinant protein was also phosphorylated by calmodulin-dependent protein kinase II. Exogenous PKG activated by 8-bromo-cGMP phosphorylated recombinant telokin when added concurrently to ileum depleted of its endogenous telokin and their relaxant effects were mutually potentiated. Based on these findings, we propose that telokin induces Ca-desensitization in smooth muscle by enhancing SMPP-1M activity and cGMP- and/or cAMP-dependent phosphorylation of telokin upregulates its relaxant effect. More studies have been carried out to test this hypothesis, to determine the physiological role of telokin and how it is regulated.
موضوع (اسم عام یاعبارت اسمی عام)
موضوع مستند نشده
Biological sciences
موضوع مستند نشده
Calcium desensitization
موضوع مستند نشده
Cyclic nucleotides
موضوع مستند نشده
Myosin
موضوع مستند نشده
Phosphatase
موضوع مستند نشده
Smooth muscle
نام شخص به منزله سر شناسه - (مسئولیت معنوی درجه اول )
مستند نام اشخاص تاييد نشده
A. V. Sombyo
مستند نام اشخاص تاييد نشده
X. Wu
دسترسی و محل الکترونیکی
نام الکترونيکي
مطالعه متن کتاب وضعیت انتشار
فرمت انتشار
p
اطلاعات رکورد کتابشناسی
نوع ماده
[Thesis]
کد کاربرگه
276903
اطلاعات دسترسی رکورد
سطح دسترسي
a
تكميل شده
Y
