Identification of a key domain in annexin and 14-3-3 proteins that stimulate calcium-dependent exocytosis in permeabilized adrenal chromaffin cells

Calcium-dependent secretion in digitonin-permeabilized adrenal chromaffin cells is stimulated by exogenous annexin II and 14-3-3 proteins. These proteins share a conserved domain that has been suggested to be involved in specific protein-protein interactions. We examined whether this domain was involved in secretion by using a synthetic peptide (P16) of sequence KGDYQKALLYLCGGDD corresponding to the C-terminus of annexin II. P16, but not truncated peptides, prevented the stimulation of secretion by 14-3-3 proteins and produced a partial inhibition of control secretion. These data suggest that the shared annexin/14-3-3 domain is important in the mechanisms controlling Ca²⁺-dependent secretion and may play a key role in protein-protein interactions during exocytosis.     

Functional role of hedgehog pathway in osteoarthritis

The hedgehog signalling pathway is one of the key regulators of metazoan development, and it plays an important role in the regulation of a variety of developmental and physiological processes. But it is aberrantly activated in many human diseases, including osteoarthritis (OA). In this study, we have reviewed the association of hedgehog signalling pathway in the development and progression of OA and evaluated the efforts to target this pathway for the prevention of OA. Usually in OA, activation of hedgehog induces up-regulation of the expression of hypertrophic markers, including type X collagen, increases production of nitric oxide and prostaglandin E2, several matrix-degrading enzymes including matrix metalloproteinase and a disintegrin and metalloproteinase with thrombospondin motifs in human knee joint cartilage leading to cartilage degeneration, and thus contributes in OA. Targeting hedgehog signalling might be a viable strategy to prevent or treat OA. Chemical inhibitors of hedgehog signalling is promising, but they cause severe side effects. Knockdown of HH gene is not an option for OA treatment in humans because it is not possible to delete HH in larger animals. Efficient knockdown of HH achieved by local delivery of small interfering RNA in future studies utilizing large animal OA models might be a more efficient approach for the prevention of OA. However, it remains a major problem to develop one single scaffold due to the different physiological functions of cartilage and subchondral bones possess. More studies are necessary to identify selective inhibitors for efficiently targeting the hedgehog pathway in clinical conditions.     

Mammalian RNA virus-derived small RNA: biogenesis and functional activity

The role of virus-derived small RNAs (vsRNAs) has been identified as an antiviral mechanism in plants, arthropods, and nematodes. Although mammalian DNA viruses have been observed to encode functional miRNAs, whether RNA virus infection generates functional vsRNAs remains under discussion. This article reviews the most recent reports regarding pathways for generating vsRNAs and the identified vsRNA activity in mammalian cells infected with RNA viruses. We also discuss several hypotheses regarding the roles of mammalian vsRNAs and comment on the potential directions for this research field.     

LncRNA882 regulates leukemia inhibitory factor (LIF) by sponging miR-15b in the endometrial epithelium cells of dairy goat

Despite the fact that long noncoding RNAs (lncRNAs) play roles in almost all biological processes, little is known about their biological function in the endometrium during the formation of endometrial receptivity. In this study, a comprehensive analysis of lncRNAs in goat endometrial tissues on Day 5 (prereceptive endometrium, PE) and Day 15 (receptive endometrium, RE) of pregnancy was performed by using RNA-Seq. As a result, 668 differentially expressed lncRNAs (DELs) were found between the PE and RE. Further study showed that lncRNA882, regulated by estrogen (E2) and progestin (P4), could act as competing endogenous RNAs (ceRNAs) for miR-15b, which inhibited the expression of transforming growth factor-b-activated kinase 1 binding protein 3 (TAB3) and then indirectly regulated the level of leukemia inhibitory factor (LIF). This was helpful for the formation of endometrial receptivity in dairy goats. In conclusion, we elucidated the endometrium lncRNA profiles of PE and RE in dairy goats; lncRNA882 acted as a ceRNA for miR-15b and then indirectly regulated the level of LIF in goat endometrial epithelium cells. Thus, this study helped us to better understand the molecular regulation of endometrial receptivity in dairy goats.     

Sievoides kocyigiti n. gen., n. sp., Mesoendothyra altineriana n. sp. and Kurnubia feleensis n. sp. from Kimmeridgian shallow water limestones intercalated with alkaline igneous rocks, Western Taurus, Turkey

In the framework of the palaeogeographical reconstruction of the Western Taurus during Jurassic, the study of northern and eastern boundary of the Taurids started. Detailed facies analysis evidenced the position of the Barla Dag ramp between two elevated areas: the southern rimmed shelf extension of the platform system and the northern neritic-beach-land plain. In the basal biostratigraphical and ecological characteristics of the Balcikhisar volcano-sedimentary sequence, correlated with the Fele outcrop, one genus and three new species of foraminifers have been found: Sievoides kocyigiti n. gen., n. sp. and Mesoendothyra altineriana n. sp. from neritic environment, and Kurnubia feleensis n. sp. from rimmed shelf lagoon. Both carbonate sedimentary deposits are intercalated with spilitic-basalt pillow lava flows. The age of the new three species is Kimmeridgian, controlled by some foraminifer golden hooks.     

The laminated sediments of Loch Ness, Scotland: Preliminary report on the construction of a chronology of sedimentation and its potential use in assessing Holocene climatic variability

Two sediment cores, ca. 6 m long, have been recovered from the north basin of Loch Ness, Scotland. Each consists of ca. 4.5 m of laminated gyttja, terminating in a basal grey, unlaminated clay. A suite of three ¹⁴C AMS dates have been obtained, and place the base of the gyttja at ca. 9500 yr B.P. Investigations into the structure, composition and formation of the laminae are in progress. Analysis by Backscatter Scanning Electron Microscopy (BSEM) has demonstrated that they consist of couplets comprising dark, clay-rich sediments thought to be deposited from spring to autumn, and pale, silt-rich layers believed to represent sedimentation through winter. The laminae are thus thought to record incidence and intensity of streamflow into the Loch over the past nine millennia, and thus illustrate environmental change over the region for most of the Holocene. X-ray densitometry has been utilised in order to count the laminations and test the hypothesis that they are varves. It has, however, proved difficult to obtain a continuous sequence of countable laminations, although it has been possible to construct a fragmented, floating chronology which indicates that the hypothesis may be correct. Examination of lamination thickness reveals that although the average rate of sedimentation throughout the time periods studied seems to have remained fairly constant, significant variations have occurred. As Loch Ness is located on the northwest oceanic fringe of Europe, any climatic signal which the laminations contain will be closely related to even larger scale events over and within the North Atlantic Ocean, which is a major controller of global climate. Preliminary statistical investigation of sequences of laminae is being carried out in order to search for periodicity of sedimentation which may then be related to appropriate climatic indices.     

Abscisic-acid-induced turion formation in Spirodela polyrrhiza L III. Specific changes in protein synthesis and translatable RNA during turion development

Abstract The developmental process leading to the formation of the abscisic acid (ABA) induced turion of Spirodela polyrrhiza was accompanied by a repression of nucleic acid and protein synthesis. DNA synthesis in the developing lurion (induced by 10⁻⁴mol m⁻³ ABA) was inhibited within 3h of ABA addition, followed by a repression of protein synthesis after 24 h, while RNA synthesis was not inhibited until 3 d. The inhibitory effect of ABA on protein synthesis was found to be selective and the synthesis of several novel proteins appeared to be induced. These effects were specific to ABA-sensitive tissue. The relationship between the changes in the protein and mRNA profiles during the development of the turion was investigated. The rapid general inhibition of protein synthesis at early stages of lurion formation could not be accounted for by the level of translatable mRNA, indicating an effect of ABA at the translational level. The specific alteration to the pattern of in vivo labelled proteins could have resulted, however, from control of the level of specific mRNAs for those particular proteins. Only after 3 d in ABA, when the developing primordium is committed to the turion developmental pathway, is there a total inhibition in the production of mRNA leading to the shutdown of all primary processes and the onset of the irreversible events leading to the dormant state.     

5.3 S RNA is a discrete cleavage product from the 5′-terminus of 18 S RNA of rat liver ribosomes

A 5.3 S RNA species observed in urea-gel electrophoretic analysis of the RNA of the small ribosomal subunit of rat liver has been identified from its sequence as the 5′-terminal 133–134 base fragment of 18 S RNA. Presumably it is cleaved by an endogenous endonuclease when the ribosomal subunits are dissociated, because it usually is not observed in 18 S RNA obtained by direct extraction of cells or tissues.