Brain spectrin(240/235) and brain spectrin(240/235E): differential expression during mouse brain development

Abstract

Mouse brain contains at least 2 distinct spectrin subtypes: brain spectrin(240/235) and brain spectrin(240/235E) (Riederer et al., 1986). In this study, we demonstrate that these subtypes are differentially expressed during mouse brain development. Brain spectrin(240/235) can be detected in fetal tissue and increases 2-fold during brain development. This subtype is enriched in the cortical cytoplasm of germinative neural cells and is also found in fibers resembling axons as early as fetal life. Brain spectrin(240/235E), which is specifically detected with antibodies to red blood cell spectrin, is below the limits of detection in fetal and neonatal brain but rapidly increases in concentration during the second postnatal week. Brain spectrin(240/235E) is confined to the cell body and dendrites of differentiating neurons and to glial cells but is not expressed in mitotic cells. This subtype is most prominent in granule cells of the cerebellum and dentate gyrus in the hippocampus.

A Dystrophin‐Immunoreactive Protein in Mammalian Brain

“…Results of immunocytochemical studies of developmental regulation of the brain spectrins were in agreement with previous work (Riederer et al, 1987). 240/ 235E brain spectrin was barely detectable at birth and through the first week (Fig.…”

Brain-specific tropomyosins TMBr-1 and TMBr-3 have distinct patterns of expression during development and in adult brain.

“…Due to their function as conductors of information in a mostly vectorial manner, neurons differ significantly from other cell types in size and geometry. Their size and shape are reflected in the neuronal cytoskeleton (1) composed of a unique set of structural proteins, such as neurofilaments, and a variety of neuron-specific actin binding proteins, such as brain-specific isoforms of myosin (2), spectrin (3), and tropomyosin (TM) (4). The process of modifying, strengthening, or eliminating synaptic connections both during and well after embryonic development has ended is now hypothesized to be the mechanism underlying such dynamic processes as learning and memory (5)(6)(7)(8).…”

Vitamin K-Dependent Carboxylation in the Developing Rat: Evidence for a Similar Mechanism of Action of Warfarin in Fetal and Adult Livers

“…Thus, microsomal proteins from fetal livers were subjected to SDS-PAGE in 10% reducing gels. As shown in Figure 1, the protein patterns of microsomes from d 16,17,18,19, and 20 fetal rats was quite similar, suggesting that the subcellular particles we had isolated indeed were derived from the same cellular organelles. The protein pattern of adult liver microsomes is also shown (Fig.…”

“…Control animals received the same quantity of saline. Warfarin-treated and control animals were killed on d 16,17,18,19, and 20 before birth, at birth (d 21) and on d 2 and 7 after birth. Before death by decapitation all rats were anesthetized with pentobarbital.…”

“…The microsomal concentration of the prothrombin precursor was measured by immunodot blotting as described by Reiderer et al (16). For this assay the microsomal pellet was dissolved in 250 mM sucrose, 25 mM imidazole, 0.5 M KCl, 1.5% Triton X-100, pH 7.2.…”