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661.
Signaling mechanisms of neurite outgrowth induced by the cell adhesion molecules NCAM and N-Cadherin
Formation of appropriate neural circuits depends on a complex interplay between extracellular guiding cues and intracellular
signaling events that result in alterations of cytoskeletal dynamics and a neurite growth response. Surface-expressed cell
adhesion molecules (CAMs) interact with the surroundings via the extracellular domain and bind to the cytoskeleton via their
intracellular domain. In addition, several CAMs induce signaling events via direct interactions with intracellular proteins
or via interactions with cell surface receptors. Thus, CAMs are obvious candidates for transmitting extracellular guidance
cues to intracellular events and thereby regulating neurite outgrowth. In this review, we focus on two CAMs, the neural cell
adhesion molecule (NCAM) and N-cadherin, and their ability to mediate signaling associated with a neurite outgrowth response.
In particular, we will focus on direct interaction between NCAM and N-cadherin with a number of intracellular partners, as
well as on their interaction with the fibroblast growth factor receptor (FGFR).
Received 23 May 2008; received after revision 14 July 2008; accepted 21 July 2008 相似文献
662.
Wang R Han G Wang J Chen G Xu R Wang L Li X Shen B Li Y 《Cellular and molecular life sciences : CMLS》2008,65(23):3851-3860
Interleukin (IL)-27 is an IL-12-related cytokine that can promote both anti- and pro-inflammatory immune responses. This study
investigated the potential role of IL-27 in autoimmune diabetes. We detected a high level of IL-27 in diabetic NOD mice. In
addition, blockade of IL-27 significantly delayed the onset of diabetic splenocyte-transferred diabetes, while IL-27-treated
diabetic splenocytes promoted the onset of the disease, compared with untreated controls. Furthermore, IL-27 up-regulated
pro-inflammatory cytokines IFN-γ and IL-17 and down-regulated anti-inflammatory cytokines IL-4, TGF-β, and IL-10 secreted
by diabetic splenocytes. These results demonstrate a pathogenic role of IL-27 in T cell-mediated autoimmune diabetes.
Received 02 September 2008; received after revision 27 September 2008; accepted 01 October 2008
R. Wang, G. Han: These authors contributed equally to this work. 相似文献
663.
Cellular pathology induced by snake venom phospholipase A2 myotoxins and neurotoxins: common aspects of their mechanisms of action 总被引:3,自引:0,他引:3
Montecucco C Gutiérrez JM Lomonte B 《Cellular and molecular life sciences : CMLS》2008,65(18):2897-2912
A large variety of snake toxins evolved from PLA2 digestive enzymes through a process of ‘accelerated evolution’. These toxins have different tissue targets, membrane receptors
and mechanisms of alteration of the cell plasma membrane. Two of the most commonly induced effects by venom PLA2s are neurotoxicity and myotoxicity. Here, we will discuss how these snake toxins achieve a similar cellular lesion, which
is evolutionarily highly conserved, despite the differences listed above. They cause an initial plasma membrane perturbation
which promotes a large increase of the cytosolic Ca2+ concentration leading to cell degeneration, following modes that we discuss in detail for muscle cells and for the neuromuscular
junction. The different systemic pathophysiological consequences caused by these toxins are not due to different mechanisms
of cell toxicity, but to the intrinsic anatomical and physiological properties of the targeted tissues and cells.
Received 05 March 2008; received after revision 08 April 2008; accepted 29 April 2008 相似文献
664.
Tang M Zhong M Shang Y Lin H Deng J Jiang H Lu H Zhang Y Zhang W 《Cellular and molecular life sciences : CMLS》2008,65(18):2924-2932
Advanced glycation end products (AGEs) play an important role in collagen deposition in diabetic cardiomyopathy. TRB3, a mammalian
homolog of Drosophila tribbles, functions to increase glucose intolerance and regulates cell proliferation. We demonstrated
that AGEs induce collagen type I expression but inhibit collagen type III expression, accompanied by increased TRB3 expression.
Furthermore, the collagen type I induced byAGEs was down-regulated after inhibition of ERK and p38-MAPK, the collagen type
III reduced by AGEs was up-regulated after inhibition of ERK. The expression of collagen types I and III regulated by AGEs
through MAPK was partly reversed after treatment with TRB3 siRNA. It suggests that the TRB3/MAPK signaling pathway participates
in the regulation of collagen types I and III by AGEs and may provide new therapeutic strategies for diabetic cardiomyopathy.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Received 08 May 2008; received after revision 25 June 2008; accepted 22 July 2008
M. Tang, M. Zhong: These two authors contributed equally to this work. 相似文献
665.
Light-harvesting complexes of vascular plants 总被引:1,自引:0,他引:1
Schmid VH 《Cellular and molecular life sciences : CMLS》2008,65(22):3619-3639
Light-harvesting complexes (LHCs) located in the thylakoid membrane of plant chloroplasts are the collectors of solar radiation
that fuel photosynthesis, and thus enable life on our planet. They consist of pigments that are non-covalently bound to light-harvesting
proteins (Lhc proteins), which form a family whose members share a significant sequence identity. Due to their central role
in photosynthesis, LHCs belong in several respects to the best-analysed membrane proteins. In the past decade, tremendous
progress has been made in identifying new members of the Lhc family, in localising the LHCs within the photosystems, and in
elucidating the structure and function of LHCs, which is summarised in this review. By contrast, gaining insight into the
assembly process and the degradation of the LHCs could not keep pace. Therefore, topics for the next decade will be the elucidation
of the location(s) and the operating mode of steps in the assembly and degradation process.
Received 15 June 2008; received after revision 1 July 2008; accepted 10 July 2008 相似文献
666.
Poulsen LR López-Marqués RL Palmgren MG 《Cellular and molecular life sciences : CMLS》2008,65(20):3119-3125
Our understanding of flippase-mediated lipid translocation and membrane vesiculation, and the involvement of P-type ATPases
in these processes is just beginning to emerge. The results obtained so far demonstrate significant complexity within this
field and point to major tasks for future research. Most importantly, biochemical characterization of P4-ATPases is required in order to clarify whether these transporters indeed are capable of catalyzing transmembrane phospholipid
flipping. The β-subunit of P4-ATPases shows unexpected similarities between the β- and γ-subunits of the Na+/K+-ATPase. It is likely that these proteins provide a similar solution to similar problems, and might have adopted similar structures
to accomplish these tasks. No P4-ATPases have been identified in the endoplasmic reticulum and it remains an intriguing possibility that, in this compartment,
P5A-ATPases are functional homologues of P4-ATPases.
Received 19 June 2008; received after revision 31 July 2008; accepted 15 August 2008 相似文献
667.
668.
Studies of the last two decades have demonstrated that sphingolipids are important signalling molecules exerting key roles
in the control of fundamental biological processes including proliferation, differentiation, motility and survival. Here we
review the role of bioactive sphingolipids such as ceramide, sphingosine, sphingosine 1-phosphate, ganglioside GM3, in the
regulation of skeletal muscle biology. The emerging picture is in favour of a complex role of these molecules, which appear
implicated in the activation of muscle resident stem cells, their proliferation and differentiation, finalized at skeletal
muscle regeneration. Moreover, they are involved in the regulation of contractile properties, tissue responsiveness to insulin
and muscle fiber trophism. Hopefully, this article will provide a framework for future investigation into the field, aimed
at establishing whether altered sphingolipid metabolism is implicated in the onset of skeletal muscle diseases and identifying
new pharmacological targets for the therapy of multiple illnesses, including muscular dystrophies and diabetes.
Received 30 April 2008; received after revision 19 June 2008; accepted 14 July 2008 相似文献
669.
Symmetric DNA sequence motifs allow the formation of palindromic protein/DNA complexes. Although symmetric protein sequence
motifs are less common, recent structural discoveries have unraveled a few protein/protein complexes with palindromic symmetry.
Remarkably, symmetric protein/protein complexes can be generated either by adjacent or remote sequence motifs, which may be
repeated or inverted. This contribution reflects and comments on recent findings of palindromic protein/protein complexes.
Received 14 May 2008; received after revision 21 June 2008; accepted 14 July 2008 相似文献
670.