Dual function of LIMK2 in endothelial cells

Various stimuli like thrombin induce endothelial cell shape change and stress fiber formation via Rho/Rho-kinase-mediated reorganization of the actin cytoskeleton. LIM-kinases regulate actin cytoskeletal reorganization through phosphorylation of cofilin at Ser3. The LIMK family kinases possess characteristic structural features, consisting of two LIM domains, a PDZ domain and a C-terminal kinase domain. In cell transfection studies it has been shown that LIMK2 is phosphorylated at Thr505 by Rho-kinase thereby activating the enzyme. Recently it has been reported that nuclear LIMKs suppress cyclin D1 expression in a manner independent of cofilin phosphorylation and actin polymerization. In this study, we found that endothelial cells express both LIMK1 and LIMK2. By using live cell imaging, we confirm previous findings that thrombin induces stress fiber formation, ruffle formation and cell contraction. Furthermore, the cell-cell contacts were disrupted and F-actin fibers connecting two cells were broken. Thrombin induced a rapid and sustained Rho-kinase activation and subsequent phosphorylation of LIM-kinase and cofilin. Pretreatment of endothelial cells with the specific Rho-kinase inhibitor Y27632 inhibited MYPT1 phosphorylation, LIM-kinase and cofilin phosphorylation and blocked stress fiber formation in thrombin-stimulated cells. Notably, thrombin induced actin stress fiber formation was abolished in cells transfected with dominant negative LIMK2. LIMK2 was mainly localized in the cytoplasm. By using Leptomycin B (a specific inhibitor of CRM-1 dependent nuclear export) and FRAP and FLIP analysis, we demonstrate that LIMK2 in resting endothelial cells shuttles between the nucleus and cytoplasm. The LIM domains of LIMK2, but not of LIMK1 inhibited its nuclear import thereby keeping LIMK2 mainly in the cytoplasm. Mutational analysis of the unique basic amino acid-rich motif (amino acids 480-503) indicated that this motif regulates the nuclear and nucleolar localization of LIMK2. Activation of PKC in PMA-stimulated endothelial cells stimulated the phosphorylation of LIMK2 at Ser283 and the translocation of LIMK2 and the PDZ-kinase construct of LIMK2 from the nucleus to the cytoplasm. Of the various PKC isoforms, PKC- and PKC- were found to be mainly responsible for Ser283 phosphorylation and the regulation of translocation of LIMK2. Mutational analysis indicated that LIMK2 phosphorylation at Ser283 and Thr494 play a role in the regulation of nucleocytoplasmic shuttling of LIMK2 by PKC. These results show that LIM-kinase activation is mediated by Rho-kinase in stimulated endothelial cells, and that LIM-kinase-mediated cofilin phosphorylation plays an essential role in thrombin-induced stress fiber formation. LIMK2 shuttles between nucleus and cytoplasm in resting endothelial cells. Phosphorylation of LIMK2 at Ser283 and Thr494 by PKC regulates nucleocytoplasmic shuttling and suggests that LIMK2 might also have a function in the nucleus such as the suppression of cyclin D1 expression

VANET: Analysis of Black hole Attack using CBR/UDP Traffic Pattern with Hash Function and GPSR Routing Protocol

With momentum of time huge development occurred in the field of MANET and VANET. As we know when new technology emerges it came with many advanages but definitely some limitation must be there. In WSN security is one of biggest challenges which we need to tackle to implement adhoc network. Main reason behind this is dynamic topology of sensing node because nodes are dynamic in nature rather than static. As technology came into existence side by side unethical activity also take place which try to access the data illegally to gain personnel profit. There are so many types of attack possibilities are there in adhoc network. Attack can be classified into active and passive. In our research article oue main concern is on black hole attack. According to this attack a malicious node with high priority number is deployed in between other nodes. Now this malicious node access the data and sends acknowledgement to source that data received. Source node will think that acknowledgement is sent by destination node but actually it is sent by malicious node.  In this research article performance analysis of the black hole attack in Vehicular Ad Hoc Network is executed

EFFICIENT SCALE INVARIENT FEATURE BASED METHOD FOR CROWD LOCALIZATION

Visual surveillance has been a very active research topic in the last few decade due to growing importance for security in the public areas. With the increasing number of CCTV networks in public areas, the enhancement in the computing power of modern computers and increase the possibility to entrust an automatic system with the security and the monitoring of events involving large crowds is within reach. Crowd detection and localization in the surveillance video is the first step in automatic crowd monitoring system. The performance of the whole system depends on this step. Detecting the crowd is a challenging task because the crowds come in different shape, size and color, against cluttered background and varying illumination conditions. As the size of the crowd increases managing the crowd becomes more complex

Survey on Image intensification using Canny Edge Technique

Image Processing is generally done in form of Signal Processing. In this images, pictures, video frame etc are given in Input form and the Output appears with certain set of features or parameters in relation to the input given. Edge Detection using Canny Technique is an set of Mathematical Functions whose main goal is to detect points in the Digital input i.e. image and detect how brightness changes variably , and where are discontinuities. Edge detection is an essential stage in processing the image. Mostly image-processing techniques consider the image as a two-dimensional signal then put standard signal-processing techniques to it. Generally it means Digital Image being processed but analog and digital signals can also be processed

Survey of Vertical Handoff Decision Criteria in LTE Cellular Networks

Vertical handover advantage brilliant importance because of the upgrades in mobility fashions by way of the Fourth era (4G) technology. A handover desire scheme in LTE networks both based totally on unmarried or multiple criteria. The wide variety of standards is right away depending on the overall handover time. In addition, the time required for deciding on a target network at some point of handover is also extended with the growth in a number of parameters. Conventional handover choice Strategies are specifically based at the unmarried parameter. But, with the advent of heterogeneous Wi-Fi networks, the overall performance of those unmarried parameter choice schemes is highly decreased. Consequently, researchers introduce multirequirements handover selection schemes. those enhancements are restricted to specific situations and for this reason do now not offer help for mounted mobility. Further, numerous schemes are proposed

Adaptive Noise Cancellation using Delta Controlled Affine Projection Algorithm

This paper presents the Adaptive No ise Cancellation using Delta Controlled Affine Projection Algorithm to adaptive filter the noise using a concept of minimum absolute mean square error. It is very simple with less computational complexity. All the computer simulations are c a dried out in Matlab software. Results are presented graphically to illustrate the improvement of performance. Performance in terms of Signal to noise ratio (SNR) is also presented in tabular form

Survey of Energy Efficient Clustering Mechanisms in Wireless Sensor Networks

Advancements in wireless communications and Micro-Electro-Mechanical structures have enabled the improvement of wireless sensor networks (WSN), which in flip have fostered the emergence of a plethora of programs in diverse fields together with agriculture, healthcare supervision, and transportation systems. However, because of the strength dilemma of battery-powered sensors, these packages nonetheless face a major energy issue that save you their giant adoption. In this thesis, we contributed to conquer this challenge via several contributions. In this paper we've got surveyed the various techniques to power efficient strategies in wi-fi sensor networks

A quantitative comparison of sRNA-based and protein-based gene regulation

Small, non-coding RNAs (sRNAs) play important roles as genetic regulators in prokaryotes. sRNAs act post-transcriptionally via complementary pairing with target mRNAs to regulate protein expression. We use a quantitative approach to compare and contrast sRNAs with conventional transcription factors (TFs) to better understand the advantages of each form of regulation. In particular, we calculate the steady-state behavior, noise properties, frequency-dependent gain (amplification), and dynamical response to large input signals of both forms of regulation. While the mean steady-state behavior of sRNA-regulated proteins exhibits a distinctive tunable threshold-linear behavior, our analysis shows that transcriptional bursting leads to significantly higher intrinsic noise in sRNA-based regulation than in TF-based regulation in a large range of expression levels and limits the ability of sRNAs to perform quantitative signaling. Nonetheless, we find that sRNAs are better than TFs at filtering noise in input signals. Additionally, we find that sRNAs allow cells to respond rapidly to large changes in input signals. These features suggest a niche for sRNAs in allowing cells to transition quickly yet reliably between distinct states. This functional niche is consistent with the widespread appearance of sRNAs in stress-response and quasi-developmental networks in prokaryotes.Comment: 26 pages, 8 figures; accepted for publication in Molecular Systems Biolog

Vertical Handoff Decision Criteria with LTE Network

A handover decision scheme in LTE networks either based on single or multiple criteria. The number of criteria is directly depending on the totalhandovertime.A vertical handover decision algorithm based on the fuzzy control theory. The algorithm takes into consider the factors of Power Level, Cost and Bandwidth. After establishing the membership functions, membership degrees of corresponding factors can be determined, which are processed by the Weight Vector. Finally, the Fuzzy Vertical Handoff Decision Vector is derived and vertical handover decision can be made. It is shown through simulation that the algorithm realizes the optimized vertical handover by evaluating and analyzing various input parameters

Algorithm for construction of portfolio of stocks using Treynor’s ratio

The aim of the paper is to implement the algorithm for selecting stocks from a pool of stocks listed in a single market index like S&P CNX 500(say) and finding the corresponding weights of the stocks in the optimized portfolio using Treynor’s ratio, on the basis of historical data of Indian stock market when the short selling is not allowed. The effectiveness of this algorithm has been demonstrated with an example