Anti-CALB2 polyclonal antibody

Background: Knowledge of gene expression kinetics around neuronal cell birth is required to dissect mechanisms underlying progenitor fate. Here, we timed cell cycle and neuronal protein silencing/induction during cell birth in the developing murine retina. Results: The pan-cell cycle markers Pcna and Mcm6 were present in the post-mitotic ganglion cell layer. Although confined to the neuroblastic layer (NBL), 67% of Ki67+ cells lacked six progenitor/cell cycle markers, and expressed neuronal markers. To define protein extinction/induction timing, we defined G2/M length throughout retinogenesis, which was typically 12 h, but <10% cells took double this time. BrdU-chase analyses revealed that at E12.5, Tubb3 (Tuj1) appeared at M-phase, followed by Calb2 and Dcx at similar to 2 h, Elavl2/3/4 at similar to 4 h, and Map2 at similar to 6 h after cell birth, and these times extended with embryonic age. Strikingly, Ki67 was not extinguished until up to a day after cell cycle exit, coinciding with exit from the NBL and induction of late markers such as Map1b/Uchl1/Rbfox3. Conclusions: A minor population of progenitors transits slowly through G2/M and, most importantly, some cell cycle proteins are retained for an unexpectedly long period in post-mitotic neurons. The high-resolution map of cell birth kinetics reported here provides a framework to better define mechanisms that regulate neurogenesis. Developmental Dynamics 241:15251544, 2012. (c) 2012 Wiley Periodicals, Inc.

The cochlear nucleus is the first central pathway involved in the processing of peripheral auditory activity. The anterior ventral cochlear nucleus (AVCN), posterior ventral cochlear nucleus (PVCN) and dorsal cochlear nucleus (DCN) each contain predominant populations of neurons that have been well characterized regarding their morphological and electrophysiological properties. Little is known, however, of the underlying genetic factors that contribute to these properties and the initial steps in auditory processing. Serial analysis of gene expression (SAGE), supported by microarray experiments, was performed on each subdivision of the rat cochlear nucleus to identify genes that may sub-serve specialized roles in the central auditory system. Pair-wise comparisons between SAGE libraries from the AVCN, PVCN and DCN were correlated with microarray experiments to identify individual transcripts with significant differential expression. Twelve highly correlated genes were identified representing cytoskeletal, vesicular, metabolic and g-protein regulating proteins. Among these were Rgs4 which showed higher expression in the DCN, Sst and Cyp11b1 with very high expression in the AVCN and Calb2 with preferential expression in the PVCN. The differential expression of these genes was validated with real-time reverse transcriptase-polymerase chain reaction. These experiments provide a basis for understanding normal auditory processing on a molecular level and a template for investigating changes that may occur in the cochlear nucleus with hearing loss, the generation and percept of tinnitus, and central auditory processing disorders. (c) 2006 IBRO. Published by Elsevier Ltd. All rights reserved.