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Annexins as Ca2+/phospholipid-binding proteins are involved in the control of many biological processes essential for plant growth and development. In a previous study, we had shown, using a proteomic approach, that the synthesis of two annexins is induced in pea roots in response to rhizobial inoculation. In this study, phylogenetic analysis identified these annexins as PsAnn4 and PsAnn8 based on their homology with annexins from other legumes. The modeling approach allowed us to estimate the structural features of these annexins that might influence their functional activity. To verify the functions of these annexins, we performed comparative proteomic analysis, experiments with calcium influx inhibitors, and localization of labeled proteins. Essential down-regulation of PsAnn4 synthesis in a non-nodulating pea mutant P56 (sym10) suggests an involvement of this annexin in the rhizobial symbiosis. Quantitative RT-PCR analysis showed that PsAnn4 was upregulated at the early stages of symbiosis development, starting from 1–3 days after inoculation to up to 5 days after inoculation, while experiments with the Ca2+ channel blocker LaCl3 revealed its negative influence on this expression. To follow the PsAnn4 protein localization in plant cells, it was fused to the fluorophores such as red fluorescent protein (RFP) and yellow fluorescent protein (YFP) and expressed under the transcriptional regulation of the 35S promoter in Nicotiana benthamiana leaves by infiltration with Agrobacterium tumefaciens. The localization of PsAnn4 in the cell wall or plasma membrane of plant cells may indicate its participation in membrane modification or ion transport. Our results suggest that PsAnn4 may play an important role during the early stages of pea-rhizobial symbiosis development.

There is increasing evidence that metalloproteinases are involved in neuropathic pain [Dev et al., Expert Opin Investig Drugs 19:455-468 ] Hence, the identification of molecules that can regulate MMP9 and MMP2 is warranted. In a recent publication, Kular et al. () claim that CCN3 functions to decrease inflammatory pain via the regulation of two metalloproteinases, MMP2 and MMP9, in response to experimentally-induced inflammation. Their conclusion is based on the following observations : i) the expression of CCN3 was reduced following induction of pain by subcutaneous injection of complete Freund's adjuvent in rat's paw, ii) an inhibition of MMP9 decreased CFA-associated mechanical allodynia, iii) inhibition of CCN3 expression by siRNA led to an upregulation of MMP2 in the dorsal horn of the spinal cord (DHSC) and MMP9 in the dorsal root ganglia (DRG), iv) a partial effect of CCN3 on CFA-induced expression of MMP9 and MMP2 in DRG and DHSC following intrathecal injection of CCN3. Unfortunately, the conclusion of this study is weakened by the lack of experimental evidence showing a direct relationship between the expression of CCN3 and MMPs. Furthermore, several results contained in this manuscript only confirm data that were previously established by others. Owing to the wide range of activities which have been attributed to CCN3 (Perbal, Mol Pathol 54:57-79 , Brigstock, J Endocrinol 178:169-175 , Perbal, Lancet 363(9402):62-64 , Perbal, Cell Commun Signal 4:6 , Holbourn et al. Trends Biochem Sci. 33:461-473 , Leask and Abraham, J Cell Sci 119:4803-4810 , Jun and Lau, Nat Rev Drug Discov 10:945-963 , Rachfal and Brigstock, Vitam Horm 70:69-103 ), the mechanisms underlying the potential role of CCN3 in the expression of these MMPs in the context of inflammatory pain must be thoroughly studied before a meaningful conclusion can be reached. Indeed, Kular et al. description of variations in CCN3, MMP9 and MMP2 levels occurring simultaneously is not sufficient to draw a functional relationship between these three proteins. It should be noted that the expression of CCN3 was already reported to repress MMP9 (Benini et al., Oncogene 24:4349-4361 , Fukunaga-Kalabis et al., Oncogene 27:2552-2560 ) and the roles of CCN3 in inflammatory processes has been extensively documented in the past few years (Bleau et al., Front Biosci 10:998-1009 , Lin et al., J Biol Chem 280:8229-8237 , Perbal, Cell Commun Signal 4:6 , Hughes et al., Diabetologia 50:1089-1098 , Lin et al., J Cell Commun Signal 4:141-153 , Pasmant et al., J Neuropathol Exp Neurol 69:60-69 , Shimoyama et al., Thromb Vasc Biol 30:675-682 , Lemaire et al., J Invest Dermatol 130:2517 , Chen and Lau, J Cell Commun Signal 4:63-69 , Le Dréau et al., Glia 58:1510-1521 , Rittié et al. J Cell Commun Signal 5:69-80 , Janune et al., J Cell Commun Signal 5:167-171 ). In addition, the expression of CCN3 in the neurons of dorsal root ganglia and dorsal horn of the spinal horn in rat and human has also been documented (Su et al., C R Acad Sci III 321:883-892 , Mol Pathol 54:184-191 , Kocialkowski et al., Anat Embryol (Berl) 203:417-427 ). Implication of CCN3 in cognitive functions (Su et al., Sheng Li Xue Bao 52:290-294 ) and the possible involvement of CCN3 in the regulation of pain was already suggested almost a decade ago (Perbal, Expert Rev Mol Diagn 3:597-604 , Perbal et al., Mol Pathol 56:80-85 ) with the demonstration of cell-specific effects of CCN3 on intracellular calcium stores and inhibition of anionic channels by CCN3 (Li et al., Mol Pathol 55:250-261 , Lombet et al., Cell Commun Signal 1:1 , Perbal, Expert Rev Mol Diagn 3:597-604 , Perbal et al., Mol Pathol 56:80-85 ). Aside from these general aspects, and in the light of the potential participation of CCN3 in the whole process of pain sensing, the reader would have appreciated the discussion in this manuscript not being essentially a flat summary of the data presented, but a more thorough discussion of the possible role for CCN3 in the regulation of MMPs and its significance in the context of the wide biological functions of CCN3. [ABSTRACT FROM AUTHOR]

Background and Scope Self-incompatibility (SI) in flowering plants ensures the maintenance of genetic diversity by ensuring outbreeding. Different genetic and mechanistic systems of SI among flowering plants suggest either multiple origins of SI or considerable evolutionary diversification. In the grasses, SI is based on two loci, S and Z, which are both polyallelic: an incompatible reaction occurs only if both S and Z alleles are matched in individual pollen with alleles of the pistil on which they alight. Such incompatibility is referred to as gametophytic SI (GSI). The mechanics of grass GSI is poorly understood relative to the well-characterized S-RNase-based single-locus GSI systems (Solanaceae, Rosaceae, Plantaginaceae), or the Papaver recognition system that triggers a calcium-dependent signalling network culminating in programmed cell death. There is every reason to suggest that the grass SI system represents yet another mechanism of SI. S and Z loci have been mapped using isozymes to linkage groups C1 and C2 of the Triticeae consensus maps in Secale, Phalaris and Lolium. Recently, in Lolium perenne, in order to finely map and identify S and Z, more closely spaced markers have been developed based on cDNA and repeat DNA sequences, in part from genomic regions syntenic between the grasses. Several genes tightly linked to the S and Z loci were identified, but so far no convincing candidate has emerged. Research and Progress From subtracted Lolium immature stigma cDNA libraries derived from S and Z genotyped individuals enriched for SI potential component genes, kinase enzyme domains, a calmodulin-dependent kinase and a peptide with several calcium (Ca2+) binding domains were identified. Preliminary findings suggest that Ca2+ signalling and phosphorylation may be involved in Lolium GSI. This is supported by the inhibition of Lolium SI by Ca2+ channel blockers lanthanum (La3+) and verapamil, and by findings of increased phosphorylation activity during an SI response. [ABSTRACT FROM PUBLISHER]

Abstract: Endocrine tumors could be defined by their ability to produce structural proteins or hormones commons to nervous and endocrine cells. They might induce physiological transforms or outcome adverse events which should be well known in order to prevent or treat them early. The goal of this review was to describe these changes, to describe preoperative assessment, and to discuss intraoperative monitoring and drugs choice based on the literature from the last 30 years. As an example, it should be noticed that: (1) preoperative blood pressure control is essential to prepare phaeochromocytoma for surgery. It should be followed during anaesthesia by intensive fluid load, reversible anaesthetic drugs and rational cardiovascular medications use (as for example remifentanil, sevoflurane, calcium channel blockers and esmolol), and after surgery by narrow clinical and biological monitoring; (2) after medullar thyroid cancer, main adverse events include cervical compressive haematoma and recurrent laryngeal nerve injury as for any thyroid surgery; (3) during pituitary surgery, air embolism might be expected, whereas water dysregulation (diabetes insipidus), corticotroph insuficiency, cerebrospinal fluid (CSF) leak might occur postoperatively. In acromegaly, difficult endotracheal intubation is possible whereas severe Cushing''s syndrome may be complicated with hypertensive cardiac failure, infections, thrombosis, delayed cicatrisation; (4) somatostatine analogs are a keystone in carcinoid tumors preoperative and anaesthetic management. [Copyright &y& Elsevier]

Abstract: In vitro treatment of mouse lymphocytes with an intracellular calcium chelator BAPTA-AM significantly decreased lectin Concanavalin-A (Con-A)-induced and mixed lymphocyte reaction (MLR) mediated, alloantigen-induced lymphocyte activation as indicated by decreased percentage of lymphoblasts among the BAPTA-treated lymphocytes. In vivo treatment of mice with intracellular Ca2+ antagonist TMB-8 was found to substantially impair delayed type hypersensitivity (DTH; cell mediated immune) response, as indicated by decreased footpad swelling on tuberculin challenge of mice sensitized with BCG, after a single treatment with a low dose of 0.01mg of TMB-8 per mouse. Interestingly, a second injection of a higher dose of TMB-8 (0.1mg per mouse) resulted in very significant (p =0.001) abrogation of DTH as indicated by complete absence of swelling of foot pad after PPD challenge in BCG-primed treated mice. All mice in this group showed fully impaired DTH response. Lymphocytes of allosensitized mice gave a significantly higher (p <0.05) MLR response than the naïve mice. However, a single treatment of allosensitized mice with 0.1mg TMB-8 resulted into a lower MLR response, comparable in magnitude to that of untreated naïve mice. [Copyright &y& Elsevier]

Annexins as Ca2+/phospholipid-binding proteins are involved in the control of many biological processes essential for plant growth and development. In a previous study, we had shown, using a proteomic approach, that the synthesis of two annexins is induced in pea roots in response to rhizobial inoculation. In this study, phylogenetic analysis identif ied these annexins as PsAnn4 and PsAnn8 based on their homology with annexins from other legumes. The modeling approach allowed us to estimate the structural features of these annexins that might inf luence their functional activity. To verify the functions of these annexins, we performed comparative proteomic analysis, experiments with calcium inf lux inhibitors, and localization of labeled proteins. Essential down-regulation of PsAnn4 synthesis in a non-nodulating pea mutant P56 (sym10) suggests an involvement of this annexin in the rhizobial symbiosis. Quantitative RT-PCR analysis showed that PsAnn4 was upregulated at the early stages of symbiosis development, starting from 1-3 days after inoculation to up to 5 days after inoculation, while experiments with the Ca2+ channel blocker LaCl3 revealed its negative inf luence on this expression. To follow the PsAnn4 protein localization in plant cells, it was fused to the f luorophores such as red f luorescent protein (RFP) and yellow f luorescent protein (YFP) and expressed under the transcriptional regulation of the 35S promoter in Nicotiana benthamiana leaves by inf iltration with Agrobacterium tumefaciens. The localization of PsAnn4 in the cell wall or plasma membrane of plant cells may indicate its participation in membrane modif ication or ion transport. Our results suggest that PsAnn4 may play an important role during the early stages of pea-rhizobial symbiosis development., (Copyright © AUTHORS.)