GPCR/endocytosis/ERK signaling/S2R is involved in the regulation of the internalization,mitochondria-targeting and-activating properties of human salivary histatin 1

Human salivary histatin 1(Hst1)exhibits a series of cell-activating properties,such as promoting cell spreading,migration,and metabolic activity.We recently have shown that fluorescently labeled Hst1(F-Hst1)targets and activates mitochondria,presenting an important molecular mechanism.However,its regulating signaling pathways remain to be elucidated.We investigated the influence of specific inhibitors of G protein-coupled receptors(GPCR),endocytosis pathways,extracellular signal-regulated kinases1/2(ERK1/2)signaling,p38 signaling,mitochondrial respiration and Na+/K+-ATPase activity on the uptake,mitochondria-targeting and-activating properties of F-Hst1.We performed a si RNA knockdown(KD)to assess the effect of Sigma-2 receptor(S2R)/Transmembrane Protein 97(TMEM97)—a recently identified target protein of Hst1.We also adopted live cell imaging to monitor the whole intracellular trafficking process of F-Hst1.Our results showed that the inhibition of cellular respiration hindered the internalization of F-Hst1.The inhibitors of GPCR,ERK1/2,phagocytosis,and clathrin-mediated endocytosis(CME)as well as siRNA KD of S2R/TMEM97 significantly reduced the uptake,which was accompanied by the nullification of the promoting effect of F-Hst1 on cell metabolic activity.Only the inhibitor of CME and KD of S2R/TMEM97 significantly compromised the mitochondria-targeting of Hst1.We further showed the intracellular trafficking and targeting process of F-Hst1,in which early endosome plays an important role.Overall,phagocytosis,CME,GPCR,ERK signaling,and S2R/TMEM97 are involved in the internalization of Hst1,while only CME and S2R/TMEM97 are critical for its subcellular targeting.The inhibition of either internalization or mitochondria-targeting of Hst1 could significantly compromise its mitochondria-activating property.

Impairment of the Regulation of Gonadal Function in Channa punctatus by Metacid-50 and Carbaryl under Laboratory and Field Conditions

Regulation of gonadal function by gonadotropic hormone (GtH) and gonadotropin-releasing hormone (GnRH) in Channa punctatus was significantly affected by nonlethal levels of Metacid-50 and Carbaryl. Under laboratory conditions, the time-dependent decrease in serum GtH level was higher in Carbaryl-treated fish than in Metacid-50-treated fish. The situation was reversed in the field, with a higher inhibitory effect of Metacid-50 being recorded. On the other hand, pituitary GtH content and GnRH activity were inhibited to a greater extent by Metacid-50 than by Carbaryl under both field and laboratory conditions. The present findings highlight that even low doses of Metacid-50 and Carbaryl are effective enough to cause reproductive damage, as evidenced by homeostatic unbalance of the reproductive regulatory system. 1990 Academic Press. Inc.

Insights into the regulation of C-repeat binding factors in plant cold signaling

Cold temperatures, a major abiotic stress, threaten the growth and development of plants, worldwide. To cope with this adverse environmental cue, plants from temperate climates have evolved an array of sophisticated mechanisms to acclimate to cold periods, increasing their ability to tolerate freezing stress. Over the last decade, significant progress has been made in determining the molecular mechanisms underpinning cold acclimation, including following the identification of several pivotal components, including candidates for cold sensors, protein kinases, and transcription factors. With these developments, we have a better understanding of the CBF-dependent cold-signaling pathway. In this review, we summarize recent progress made in elucidating the cold-signaling pathways, especially the C-repeat binding factor-dependent pathway, and describe the regulatory function of the crucial components of plant cold signaling. We also discuss the unsolved questions that should be the focus of future work.

The medial preoptic area and the regulation of parental behavior

The preoptic area （POA） is located in the most anterior part of the hypothalamus and is bordered dorsally by the anterior commissure and anteroventrally by the nucleus of the diagonal band of Broca[1]. Accumulating evidence from developmental neurobiology suggests, however, that the POA may be a separate entity from hypothalamus, and may actually be part of the basal telencephalon[2,3]. Both the hypothalamus and POA are highly complex and heterogeneous areas, containing multiple nuclei, each of which has specific fundamental functions for survival. Among these, the POA contains nuclei involved in the regulation of blood osmolality and temperature （the median preoptic nucleus）, sleep （the ventrolateral preoptic and suprachiasmatic nuclei）, ovulation （gonadotropin-releasing hormone neurons scattered mainly in the ventral part of the POA）, male sexual behavior （the medial preoptic nucleus）, and parental behavior （the central part of the medial POA, cMPOA）.

THE PIGMENT-PROTEIN COMPLEXES OF HIGHER PLANTS MIGRATION IN THYLAKOID AND THE REGULATION OF LIGHT ENERGY DISTRIBUTION BETWEEN PHOTOSYSTEMS

Appressed and non-appressed lamella membranes of Castor bean leaf chloroplasts were separated by non-ionic detergent Triton-X 100.Appressed membranes showed a high oxygen-evolving activity and low chl a/b ratio. Examining with SDS-PTGE and liquid nitrogen temperature fluorescence measurement showed that they contained only PSII and light-harvesting pigment-protein complexes (LHCP),and there was no detectable amount of PSI. Freeze-fracture electromicroscopic observation confirmed that this part was really an appressed lamella membrane. Through divalent cation Mg^(++), the thylakoid membranes were induced to unstack and restack.With the addition of Mg^(++), the fluorescence intensity was changed instantly. We realized that there existed two processes:One was a rapid process which was accomplished within 30 s. The other was a slow process of which the time duration was about 60 min. This dual effects of Mg^(++) had not been reported before.We had analyzed the change of F685/F730 and discussed the possible rneehanis ms of light energy distribution between photosystems.

NDGA ameliorates experimental autoimmune encephalomyelitis via the regulation of IL-6,IL-17 and TGF-b

Objective To investigate the effets of nordihydroguaiaretic acid(NDGA)on the expression of IL-6,IL-17and TGF-βin mice with experimental autoimmune encephalomyelitis(EAE).Methods C57BL/6 mice were immunized with MOG35-55 to induce EAE.The 54 mice were randomly and equally divided into control group,model group and treatment group.Mice in treatment