Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Regulators of G-protein signalling: a novel protein family involved in timely deactivation and desensitization of signalling via heterotrimeric G proteins (1999)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 360 (1999), S. 14-26 
    Details
    ISSN: 1432-1912
    Keywords: Key words Heterotrimeric G proteins ; GTPase-activating proteins ; RGS proteins ; Recovery ; Desensitization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In a variety of signalling pathways heterotrimeric guanine-nucleotide-binding proteins (G proteins) trigger physiological responses elicited by hormones, neurotransmitters and sensory stimuli. Receptor-induced GDP/ GTP exchange activates G proteins by dissociating G-protein α-subunits from the βγ-dimers. Both α-subunits and βγ-dimers are involved in effector regulation. The deactivation of these active forms is controlled by the hydrolysis of GTP bound to α-subunits, allowing the inactive heterotrimer to reform. Termination of G-protein-mediated signalling in vivo is 10- to 100-fold faster than the in vitro rate of GTP hydrolysis by α-subunits, suggesting that in analogy to the GTPases of the Ras-superfamily, GTPase-activating proteins (GAPs) are required to achieve timely deactivation. Recently, members of a novel protein superfamily, known as “regulators of G-protein signalling” (RGS), were identified as potent GAPs for at least one subset of heterotrimeric G-protein α-subunits. In this review, we intend to discuss the proposed mechanism by which RGS proteins exert GAP activity for G-protein α-subunits as well as their specificities. The role of RGS proteins in desensitization and temporal resolution in certain signalling pathways will also be addressed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002109900031
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Sexual differences in bone markers and bone mineral density of normal Chinese (1996)
    Springer
    Calcified tissue international 59 (1996), S. 454-460 
    Details
    ISSN: 1432-0827
    Keywords: Osteocalcin ; Procollagen-I C terminal peptide ; Bone alkaline phosphatase ; N-teleopeptide type I collagen ; Bone mineral density ; Chinese men and women
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract We measured bone mineral density (BMD) at lumbar (L2–L4) vertebrae and proximal femurs of 385 healthy Chinese women aged 40–70 years and 156 healthy Chinese men aged 20–85, and four markers—bone alkaline phosphatase isozyme (BAP), procollagen-I C terminal propeptide (PICP), osteocalcin (BGP) in serum, and a bone resorption marker, urinary cross-linked N-telopeptide of type I collagen (NTX), of these subjects. The results indicate that in postmenopausal women, levels of all the markers increased with age. In men, serum BAP, PICP, and urinary NTX decreased significantly, and serum BGP decreased with borderline significance (P=0.08). With increasing age, bone density decreased at both sites in post-menopausal women and at the proximal femur in men. The lumbar bone density showed no significant age-related changes in men. In premenopausal women, BMD at either site showed no significant change with increasing age. Despite the different trends between men and women of agerelated changes in BMD and bone markers, bone density of both proximal femur and spine in both sexes correlated inversely with levels of the bone markers in a manner independent of age or body weight. The meaning of opposite age effects on bone markers in men and women needs further investigation. In addition, higher bone marker levels, implying faster bone turnover rate, are associated with lower BMD in both sexes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00369210
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...