全國中小學科展

一等獎

探討神經細胞特異性磷酸化PaxillinS119的進核機制與其對 RNA剪接的調控

神經細胞成熟的過程中可分成數個階段,每個階段間的轉換都伴隨著蛋白質的種類,RNA異構體、細胞結構與功能等全面性的轉變。但控制神經細胞在確切的時序下成熟的分子機制尚待研究。本研究發現 Paxillin 的新功能:當腦神經細胞在活體外培養至第七天時, Paxillin 的位點 Serine119 會被磷酸化 (p-PaxillinS119),並從細胞質轉位進入至細胞核。我們使用 N2a 細胞以神經分化的模式來探討 p-PaxillinS119 進核的分子機制與功能,發現 p-PaxillinS119 進入細胞核需要位點 Serine119 被磷酸化,且分析後確認 Paxillin 的 LIM 結構域中帶有 PY-NLS 序列,分別為 P516/Y517 及 P575/Y576。我們發現 Paxillin 藉由轉運蛋白 Importin β2 辨識其 PY-NLS序列,進行蛋白間的交互作用後進入細胞核中。從螢光影像的分析,我們觀察到神經細胞的 p-PaxillinS119 在細胞核中會呈現顆粒狀,並與 RNA 剪接因子 P-SR 共定位在核斑點上。經由免疫共沉澱與細胞轉染的方式,我們證實位點 Serine119 突變,會影響 Paxillin 與 RNA 剪接因子的交互作用,及降低細胞分化與 RNA 剪接的程度。

Silver Moringa Cloth: Silver Nanoparticle Fabric Based on Moringa Extract (Moringa oleifera) as Antibacterial Against Methicilin Resistant Staphylococcus aureus

Staphylococcus aureus is addressed as one of the most common pathogens in hospital settings and in the community. This pathogen causes invasive infections, sepsis, and death. The emergence of antibiotic-resistant bacteria is due to bacterial mutations and the use of antibiotic drugs that are not by procedures. Resistance makes MRSA infections difficult to treat, resulting in high healthcare costs. These problems lead to an urgent need to find alternative drugs to control MRSA infection. Therefore, developing new drugs and procedures such as antibacterial nanoparticles, are particularly promising. Indonesia has many medicinal plants with antibiotic activity, including Moringa oleifera. Moringa oleifera contains several active compounds such as alkaloids, flavonoids, and saponins which are known to have antibiotic activity. Silver nanoparticles or AgNPs are currently used as antimicrobial agents because they are toxic to prokaryotic cells (bacteria) but relatively safe for eukaryotic cells. AgNP synthesis mediated by M. oleifera extract has the advantages of being non-toxic, pollution-free, and environmentally friendly. Sisal is a potential source of naturally derived fabric and a prospective source of multifunctional textiles. Recent studies have utilized and functionalized sisal to develop composite materials. However, functionalizing of sisal using nanosilver-based materials has not been studied yet. Bioactive chemicals from plant-extracted nanoparticles also provide additional antimicrobial properties. This study aims to produce AgNPs mediated by M. oleifera leaf extract and to analyze its antimicrobial effect on MRSA growth. The powdered Moringa (4g) was boiled with 100 ml of distilled water (550 C) for 15 minutes. The mixture was filtered through Whatman No 1 filter paper and store refrigerated. The nanoparticle was synthesized by rinsing sisal fabric cloth to several concentrations of AgNO3 (1mM, 10mM, and 20mM) with Moringa extract. Nanoparticle synthesis from AgNO3 done with the help of Moringa oleifera extract. The resulting AgNPs have MIC values (Minimum Inhibitory Concentration) and MBC (Minimum Bacteriocidal Concentration) of 1.25 mg/ml. The resulting silver nanoparticles showed antibiotic activity against MRSA with an average inhibition zone diameter of 15.677 mm. XRD and SEM studies are going to be held to support the data.