The Osmia cornifrons plays an important role in pollinating fruit trees, such as apple trees. To better understand diapause and oviposition in O. cornifrons, we investigated the correlation between the ovarian development and secretion level of OcVg protein in hemolymph. During ovarian development in wintering the number of oocytes progressively increased in comparison with the length of the ovaries and the oocytes. After emergence, the oocyte and ovary sizes developed until 6 days after emergence and declined after 6 days, but the number of oocytes decreased gradually. The secretion level of OcVg protein in hemolymph revealed that during wintering, the secretion level increased from 1 month to 2 months and then stagnated after 2 months. After diapause, the secretion level increased gradually until day 6 of the newly emerged adult from cocoon stage, and thereafter gradually declined, remaining detectable until day 30 of the adult stage. The correction analysis between ovarian development and OcVg secretion level in hemolymph found that in wintering, the number of oocytes was positively correlated to OcVg secretion level. After diapause, the ovary and first oocyte lengths and the number of oocytes showed significant changes in OcVg secretion level and positively correlated with OcVg secretion level, respectively. These results suggest that there is a significant interaction between ovarian development and the secretion level of OcVg protein and the pattern of ovarian development and secretion of OcVg protein are stage-specific in the O. cornifrons female.

Microtubule-associated protein 1B (MAP1B), a member of MAP1 family, plays a key role in the brain development. MAP1B binds to many kinds of proteins directly or indirectly. In our previous studies, MAP1B and glyceraldehydes 3-phosphate dehydrogenase (GAPDH) were down-regulated in bovine follicular cystic follicles (FCF). This study was performed to examine interaction between MAP1B and GAPDH in bovine follicles using immunoprecipitation (IP) with western blot analysis and immunohistochemisty. MAP1B and GAPDH mRNA expression levels were down-regulated in bovine FCFs. Consistent with the semi-quantitative PCR data, their protein expressions were also down-regulated in FCFs. IP data showed that MAP1B bound to GAPDH in normal follicles, but their binding was absent in FCFs, suggesting that these data might be resulted from a low level of MAP1B and/or GAPDH expression. These results suggest that GAPDH does not as always function as a loading control in bovine follicles.

Interferon induced transmembrane protein-1 (IFITM1) is one of transmembrane protein which is differentially expressed in uterus during estrus cycle and pregnancy, that IFITM1 gene is highly expressed in estrus stage by the effect of estrogen, and in parturition by the effect of PGF2 alpha. This genes are also up-regulated in cells with hyperactivation of the WNT/β-catenin signaling pathway. In this study, to identify a function of IFITM1, the binding partner of IFITM1 were determined using immunoprecipitation and LC- MASSMASS methods. 1, 3 and 5 ug of polyclonal anti-IFITM1 antisera were used for immunoprecipitation, and the 75 kDa of specific band was detected in silver stained polyacylamide gel. This band were chracterized using LC-MASS-MASS, and revealed this band is glucose regulated protein 75 (GRP75) which binds to p53 and inhibits the p53 action in nucleus. To identify the localization of GRP75 in cells, immunocytochemical approach has been applied, and GRP75 is expressed in mitochondria of L929 murine connective tissue cells. Co-localization study between IFITM1 and GRP75 in L929 cell identified that these two proteins were closely expressed in mitochondria. Although the role of the interaction of these two protein need to be clarified in various biological phenomena, this data suggest that close interaction of IFITM1 and GRP75 may regulate cellular functions in uterus on sets of estrus cycle and pregnancy.

The neurotrophin plays an important role in the development, differentiation and survival of the nervous system in vertebrates. It exerts its cellular effects through two different receptors, the Trk receptor tyrosine kinase neurotrophin receptor and the p75 neurotrophin receptor, a member of the tumor necrosis factor receptor superfamily. Trk and p75 neurotrophin receptors utilize specific target proteins to transmit signals into the cell. An ankyrin-rich membrane spanning protein (ARMS) was identified as a new p75 interacting protein and serves as a novel downstream target of p75 neurotrophin receptor. We sought to delineate the interaction between p75 and ARMS by deletion constructs of p75 and green fluorescent protein (GFP)-tagged ARMS. We examined the interaction between these two proteins after overexpressing them in HEK-293 cells. Using both Western blot analysis and immunocytochemistry followed by confocal laser scanning microscopy, we found out that the intracellular domain of the p75 neurotrophin receptor was important for the interaction with ARMS. The results from this study suggest that ARMS may play an important role for mediating the signals from p75 neurotrophin receptor into the cell.

ASKl(apoptosis signal-regulating kinase 1) is an important mediator of a poptotic s ignaling initi ated by a variety of death stimuli, including tumor necrosis factor ‘ Fas activat ion, oxidative st ress, and DNA damage. It was originally discovered as a mitogen -activated protein kinase kinase kinase(MAP3K) with proapoptotic activ ity Wben the A8Kl is stimulated, it activates both the MKK4/MKK7-JNK pathway and the M와(3/MKK6- p38 ki nase pathway‘ leading to stress responses or apoptosis. Owing to its critical role in promoting apoptosis. ASKl activity is highly control led in cells by multiple mechanisrns, includ ing phos ph이 ylation ， oligomeri zation, and protein protein inte ractions. Phosphorylation of A8Kl at Thr-845 has been correlated with its acti vation . while phos phorylation at 8er-83 by Akt/protein kinase B attenuates A8Kl activity . It has also been demonst rated that in tramol ecular interaction, probably between the NH2• terminal and COOH-terminal domains of ASKl, may be required to maintain A8Kl in its inactive state, whereas oligomeri zation of its COOH- terminal domains is correlated with ASKl activation. The most commonly observed means of ASKl regulation, however, is thrO\땅h protein-protein in teractions. Numerous proteins have been shown to bind ASKl to exert theiJ‘ reg버atory function. For example. binding of TRAF2 0 1' Daxx promotes ASK1 funct ion, whereas the kinase and proapoptotic activities of A8Kl a re inhibited by many other associated proteins, including reduced t hi oredoxin, glutaredoxin, Cdc25A‘ Hsp 72, A8Kl - in teracting protein 1. and 14-3-3 proteins. A novel mechan ism of the anti-apoptotic action of Raf-l via phys ical interaction with ASKl wi ll be described. Furthermore, signifi cance of phosphorylati on s ite of 8er-1034 in the C-terminal regula tory domain of A8Klin the apoptotic activity wil l be discussed

The germline stem cells of the Drosophila ovary continuously produce eggs throughout the life- span. Intricate regulation of stemness and differentiation is critical to this continuous production. The translational regulator Nos is an intrinsic factor that is required for maintenance of stemness in germline stem cells. Nos expression is reduced in differentiating cells at the post-transcriptional level by diverse translational regulators. However, molecular mechanisms underlying Nos repression are not completely understood. Through three distinct protein-protein interaction experiments, we identified specific molecular interactions between translational regulators involved in Nos repression. Our findings suggest a model in which protein complexes assemble on the 3’ untranslated region of Nos mRNA in order to regulate Nos expression at the posttranscriptional level.

The plant hormone abscisic acid (ABA) serves as an integrator of environmental stress such as drought, to trigger stomatal closure by regulating specific ion channels in guard cells. We previously reported that SLAC1, an outward anion channel required for stomtal closure, was regulated via reversible protein phosphorylation events involving ABA signaling components including protein phosphatase 2C members and a SnRK2-type kinase (OST1). In this study, we reconstituted the ABA signaling pathway as a protein-protein interaction relay from the PYL/RCAR type receptors, to the PP2C-SnRK2 phosphatase-kinase pairs, to the ion channel SLAC1. The ABA receptors interact with and inhibit PP2C phosphatase activity against the SnRK2-type kinase, releasing active SnRK2 kinase to phosphorylate and activate the SLAC1 channel, leading to reduced guard cell turgor and stomatal closure. Both yeast-two hybrid and bi-molecular fluorescence complementation assays were used to verify the interactions among the components in the pathway. The biochemical assays demonstrated the activity modifications of phosphatases and kinases by their interaction partners. The SLAC1 channel activity was used as a readout for the strength of the signaling pathway depending on the presence of different combinations of signaling components.