We report on a computational model of retinal motion sensitivity based on correlation-based motion detectors. We simulate object motion detection in the presence of retinal slip caused by the salamander's head movements during locomotion. Our study offers new insights into object motion sensitive ganglion cells in the salamander retina. A sigmoidal transformation of the spatially and temporally...

This study examines how signals generated in the oculomotor cerebellum could be involved in the control of gaze shifts, which rapidly redirect the eyes from one object to another. Neurons in the caudal fastigial nucleus (cFN), the output of the oculomotor cerebellum, discharged when monkeys made horizontal head-unrestrained gaze shifts, composed of an eye saccade and a head movement. Eighty-sev...

Cell movements during lens development and differentiation involve dynamic regulation of cell-matrix and cell-cell adhesion. How these processes are regulated depends on the particular array of matrix components and adhesion proteins that are expressed, as well as the signaling pathways that affect them. This review examines what is known about adhesion proteins and their regulation in the lens...

During animal gastrulation, the specification of the embryonic axes is accompanied by epithelio-mesenchymal transition (EMT), the first major change in cell shape after fertilization. EMT takes place in disparate topographical arrangements, such as the circular blastopore of amphibians, the straight primitive streak of birds and mammals or in intermediate gastrulation forms of other amniotes su...

a closed form three-dimensional solution is presented for determination of the local buckling (cell buckling) load of the nanosheets. moreover, an expression is proposed for the effective 2d young’s modulus of the unit cell of the nanosheet. in this regard, a three-dimensional efficient space-frame-like geometrical model with angular and extensional compliances is considered to investigate stab...

The electrically induced movements of outer hair cells (OHC) were studied using the whole-cell voltage-clamp technique and video analysis. Cell shortening occurs during depolarization and elongation occurs during hyperpolarization from holding potentials near -70 mV. However, a marked asymmetry in response magnitude exists such that depolarization produces larger cell length changes than do com...

Gastrulation of Drosophila melanogaster proceeds through sequential cell movements: ventral mesodermal (VM) cells are induced by secreted Fog protein to constrict their apical surfaces to form the ventral furrow, and subsequently lateral mesodermal (LM) cells involute toward the furrow. How these cell movements are organized remains elusive. Here, we observed that LM cells extended apical protr...

Various signaling pathways regulate shaping of the main body axis during early vertebrate development. Here, we focused on the role of protein-tyrosine phosphatase signaling in convergence and extension cell movements. We identified Ptpn20 as a structural paralogue of PTP-BL and both phosphatases were required for normal gastrulation cell movements. Interestingly, knockdowns of PTP-BL and Ptpn2...

beta-Arrestin 2 (betaarr2) is a multifunctional protein that regulates numerous aspects of G-protein-coupled receptor function. However, its possible involvement in developmental processes is poorly understood. In this work, we examined the potential role of betaarr2 during Xenopus early development. Gain- and loss-of-function studies showed that Xenopus betaarr2 (xbetaarr2) is required for pro...