Serine threonine kinase receptor associated protein regulates early follicle development in the mouse ovary.

The molecular mechanisms involved in regulating the development of small, gonadotrophin-independent follicles are poorly understood; however, many studies have highlighted an essential role for TGFB ligands. Canonical TGFB signalling is dependent upon intracellular SMAD proteins that regulate transcription. STRAP has been identified in other tissues as an inhibitor of the TGFB-SMAD signalling pathway. Therefore, in this study we aimed to determine the expression and role of STRAP in the context of early follicle development. Using qPCR, Strap, Smad3 and Smad7 revealed similar expression profiles in immature ovaries from mice aged 4-16 days containing different populations of early growing follicles. STRAP and SMAD2/3 proteins co-localised in granulosa cells of small follicles using immunofluorescence. Using an established culture model, neonatal mouse ovary fragments with a high density of small non-growing follicles were used to examine the effects of Strap knockdown using siRNA and STRAP protein inhibition by immuno-neutralisation. Both interventions caused a reduction in the proportion of small, non-growing follicles and an increase in the proportion and size of growing follicles in comparison to untreated controls, suggesting inhibition of STRAP facilitates follicle activation. Recombinant STRAP protein had no effect on small, non-growing follicles, but increased the mean oocyte size of growing follicles in the neonatal ovary model and also promoted the growth of isolated preantral follicles in vitro Overall findings indicate STRAP is expressed in the mouse ovary and is capable of regulating development of small follicles in a stage-dependent manner

The structures of natively assembled clathrin-coated vesicles

Clathrin-coated vesicles mediate trafficking of proteins and nutrients in the cell and between organelles. Proteins included in the clathrin-coated vesicles (CCVs) category include clathrin heavy chain (CHC), clathrin light chain (CLC), and a variety of adaptor protein complexes. Much is known about the structures of the individual CCV components, but data are lacking about the structures of the fully assembled complexes together with membrane and in complex with cargo. Here, we determined the structures of natively assembled CCVs in a variety of geometries. We show that the adaptor β2 appendages crosslink adjacent CHC β-propellers and that the appendage densities are enriched in CCV hexagonal faces. We resolve how adaptor protein 2 and other associated factors in hexagonal faces form an assembly hub with an extensive web of interactions between neighboring β-propellers and propose a structural model that explains how adaptor binding can direct the formation of pentagonal and hexagonal faces

Design and fabrication of biodiesel mixer for the compatibility study of biodiesel blends with automotive part material

Biodiesel is a way or alternative to replacing pure fossil fuel where it likely going exhaust and may run out totally. Biodiesel is a mixture of sentence percentage of diesel oil and it will combine it with suitable organic substance. However, seems like not all of raw material that will combine with biodiesel compound is suitable and an analysis should be done before a massive production of sector automotive take place by using that raw material. The mixture of biodiesel and raw material usually been done with small beaker which is the testing space is limited. Therefore, this final year project is focusing on design and fabrication a biodiesel mixer which can replace recent testing toward compatibility study of automotive material. In addition, each of criteria of biodiesel mixer needs to be similar to recent analysis method. Each of the specimens can be hang on the biodiesel container in sentence of time to study the material is suitable or not. Besides that, all tools and equipment that being uses in fabrication of biodiesel mixer needs compatibility enough with biodiesel to avoid error while testing took place. Thus, this project will make the researcher done an analysis easier compare to recent method toward compatibility study of biodiesel mixed with automotive material

SMAD3 directly regulates cell cycle genes to maintain arrest in granulosa cells of mouse primordial follicles

Primordial follicles, consisting of granulosa cell (GC)-enveloped oocytes are maintained in a state of developmental arrest until activated to grow. The mechanism that operates to maintain this arrested state in GCs is currently unknown. Here, we show the TGFβ-activated transcription factor SMAD3 is expressed in primordial GC nuclei alongside the cell cycle proteins, cyclin D2 (CCND2) and P27. Using neonatal C57/Bl6 mouse ovaries densely populated with primordial follicles, CCND2 protein co-localised and was detected in complex with P27 by immunofluorescence and co-immunoprecipitation, respectively. In the same tissue, SMAD3 co-precipitated with DNA sequences upstream of Ccnd2 and Myc transcription start sites implicating both as direct SMAD3 targets. In older ovaries follicle growth was associated with nuclear exclusion of SMAD3 and reduced P27 and CCND2 in GCs, alongside elevated Myc expression. Brief (2 H) exposure of neonatal ovaries to TGFβ1 (10 ng/ml) in vitro led to immediate dissociation of SMAD3 from the Ccnd2 and Myc promoters. This coincided with elevated Myc and phospho-S6, an indicator of mTOR signalling, followed by a small increase in mean primordial GC number after 48 H. These findings highlight a concentration-dependent role for TGFβ signalling in the maintenance and activation of primordial follicles, through SMAD-dependent and independent signalling pathways, respectively

Catch Composition of Set Net Fisheries During Normal Season in Sungai Sembilang Waters, Selangor, Malaysia

Highlight ResearchThe Set Net was identified and recorded.Length and weight of the catch of set net was analyzed. AbstractSet net fisheries are made according to traditional fishing gears method in the coastal waters of Sungai Sembilang, Selangor, Peninsular Malaysia. These fisheries system are the passive structure of gear used to catch fish that swim in shallow water with muddy substrate. This study focused on determining the species variety and the possible future of set net fisheries in Sungai Sembilang. Catch composition of set net was investigated based on the catch data during July to December 2020 and continued from January to February 2021. The catch data was recorded by a research assistant on site during fishing season. The data consist of species, length and weight of all catches recorded. Total catch of 60 fish species belonging to 23 families were captured during this study period. Ariidae (31.73%), Clupeidae (11.56%), and Scatophagidae (7.96%) were determined as dominant families caught this set net. The total dominant catch amount of species Plicofollis argyropleuron (18.71%), Nemapteryx caelata (9.96%), and Anodontostoma chacunda (8.92%) compromised 37.6% of the total catch. This type of fishing gear can be used by local fisherman to catch fishes and can prevent trawl net from come closer to the shore. This study would provide some general useful information about the status of set net fisheries as well as the species abundance caught from the set net

Imaging ultrafast dynamics on the nanoscale with THz-STM

The ability to directly image ultrafast phenomena with nanometer spatial resolution is essential to our understanding of local excitation dynamics in nanomaterials and devices. We have developed a new approach to ultrafast scanning tunneling microscopy (STM) that couples terahertz (THz) pulses to the scanning tip of a STM. We have used THz-STM under ambient lab conditions to image ultrafast charging dynamics of a single InAs nanodot on GaAs with 0.5 ps time resolution and 2 nm spatial resolution. We are currently developing THz-STM for operation in ultrahigh vacuum with the goal of imaging ultrafast dynamics on surfaces with atomic resolution