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The actin-rich cortex plays a fundamental role in many cellular processes. Its architecture and molecular composition vary across cell types and physiological states. The full complement of actin assembly factors driving cortex formation and how their activities are spatiotemporally regulated remain to be fully elucidated. Using Dictyostelium as a model for polarized and rapidly migrating cells, we show that GxcM, a RhoGEF localized specifically in the rear of migrating cells, functions together with F-BAR protein Fbp17, a small GTPase RacC, and the actin nucleation-promoting factor WASP to coordinately promote Arp2/3 complex-mediated cortical actin assembly. Overactivation of this signaling cascade leads to excessive actin polymerization in the rear cortex, whereas its disruption causes defects in cortical integrity and function. Therefore, apart from its well-defined role in the formation of the protrusions at the cell front, the Arp2/3 complex-based actin carries out a previously unappreciated function in building the rear cortical subcompartment in rapidly migrating cells.

Polarity is essential for diverse functions in many cell types. Establishing polarity requires targeting a network of specific signaling and cytoskeleton molecules to different subregions of the cell, yet the full complement of polarity regulators and how their activities are integrated over space and time to form morphologically and functionally distinct domains remain to be uncovered. Here, by using the model system Dictyostelium and exploiting the characteristic chemoattractant-stimulated translocation of polarly distributed molecules, we developed a proteomic screening approach, through which we identified a leucine-rich repeat domain–containing protein we named Leep1 as a novel polarity regulator. We combined imaging, biochemical, and phenotypic analyses to demonstrate that Leep1 localizes selectively at the leading edge of cells by binding to PIP3, where it modulates pseudopod and macropinocytic cup dynamics by negatively regulating the Scar/WAVE complex. The spatiotemporal coordination of PIP3 signaling, Leep1, and the Scar/WAVE complex provides a cellular mechanism for organizing protrusive structures at the leading edge.

A satisfaction and dissatisfaction level within an individual influences the motivation level and his/her performance throughout the life. When an individual is satisfied with his/her work, he/she gets pleasure and feels motivated. Obtaining satisfaction from their education system is very important for students as this will lead to better learning possibilities. This paper aims to compare the level of academic satisfaction among the students of Traditional Education System and Open Education System. This paper also investigates academic satisfaction of urban and rural based students and comparing them over traditional (Urban: 110; Rural: 90), and open (Urban: 80; Rural: 71) education system. Statistical tests demonstrate that there is significant difference in the level of academic satisfaction among the students of Open Education System (OES) and Traditional Education System (TES). (Contains 12 tables and 5 figures.)

Motivation plays a crucial role in learning. Motivation energizes the behavior of the individual. It also directs the behavior towards specific goals. It helps students acquire knowledge, develop social qualities, increase initiation, persist in activities, improve performance, and develop a sense of discipline. This paper aims to compare the levels of motivation between students in the open education system (OES) and in the traditional education system (TES) in India. The study further investigates the motivation levels of male and female students in the two systems. An Academic Motivation Scale was prepared and administered on the students of TES (n = 200) and OES (n = 151). Results show that there exist significant differences in the level of motivation between the students of TES and OES. The study concludes that it is the presence or absence of extrinsic motivation which is predominantly responsible for this difference. (Contains 6 tables and 6 figures.)

Higher education today is being viewed as a tool to achieve prosperity and high living standards. It is thus looked upon as a service to the society and a powerful weapon to change the society for its betterment. Motivation plays a crucial role in learning. Motivation energizes the behavior of the individual. It also directs the behavior towards specific goals. It helps in acquisition of knowledge, develops social qualities, increases initiation of persistence in activities, leads to improved performance and develops a sense of discipline in the individual. This paper aims to compare Open Education System and Traditional Education System with respect to Academic Motivation of students towards the two types of education systems. This paper also tries to compare the academic motivation of rural and urban based students. It has been found in this paper that there is significant different in Academic Motivation among students of the two types of education systems. The significant difference in academic motivation has also been found in urban and rural based students, compared between the two systems. The paper has also forwarded some suggestions which may be considered by the policy makers and administrators of OES to help increase the academic motivation of students of OES. (Contains 8 tables.)