The Importance of Brain Banks for Molecular Neuropathological Research: The New South Wales Tissue Resource Centre Experience

New developments in molecular neuropathology have evoked increased demands for postmortem human brain tissue. The New South Wales Tissue Resource Centre (TRC) at The University of Sydney has grown from a small tissue collection into one of the leading international brain banking facilities, which operates with best practice and quality control protocols. The focus of this tissue collection is on schizophrenia and allied disorders, alcohol use disorders and controls. This review highlights changes in TRC operational procedures dictated by modern neuroscience, and provides examples of applications of modern molecular techniques to study the neuropathogenesis of many different brain disorders

The regulatable MAL32 promoter in S. cerevisiae: characteristics and tools to facilitate its use

Here we describe a set of tools to facilitate the use of maltose and the MAL32 promoter for regulated gene expression in yeast, alone or in combination with the GAL1 promoter. Using fluorescent protein reporters we find that under non-inducing conditions the MAL32 promoter exhibits a low basal level of expression, similar to the GAL1 promoter, and that both promoters can be induced independently of each other using the respective sugars, maltose and galactose. While their repression upon glucose addition is immediate and complete, we found that the MAL32 and GAL1 promoter each exhibit distinct induction kinetics. A set of plasmids is available to facilitate the application of the MAL32 promoter for chromosomal modifications using PCR targeting and for plasmid based gene expression. This article is protected by copyright. All rights reserved.status: publishe

Extracellular 2′,3′-cAMP Is a Source of Adenosine*

We discovered that renal injury releases 2′,3′-cAMP (positional isomer of 3′,5′-cAMP) into the interstitium. This finding motivated a novel hypothesis: renal injury leads to activation of an extracellular 2′,3′-cAMP-adenosine pathway (i.e. metabolism of extracellular 2′,3′-cAMP to 3′-AMP and 2′-AMP, which are metabolized to adenosine, a retaliatory metabolite). In isolated rat kidneys, arterial infusions of 2′,3′-cAMP (30 μmol/liter) increased the mean venous secretion of 3′-AMP (3,400-fold), 2′-AMP (26,000-fold), adenosine (53-fold), and inosine (adenosine metabolite, 30-fold). Renal injury with metabolic inhibitors increased the mean secretion of 2′,3′-cAMP (29-fold), 3′-AMP (16-fold), 2′-AMP (10-fold), adenosine (4.2-fold), and inosine (6.1-fold) while slightly increasing 5′-AMP (2.4-fold). Arterial infusions of 2′-AMP and 3′-AMP increased secretion of adenosine and inosine similar to that achieved by 5′-AMP. Renal artery infusions of 2′,3′-cAMP in vivo increased urinary excretion of 2′-AMP, 3′-AMP and adenosine, and infusions of 2′-AMP and 3′-AMP increased urinary excretion of adenosine as efficiently as 5′-AMP. The implications are that 1) in intact organs, 2′-AMP and 3′-AMP are converted to adenosine as efficiently as 5′-AMP (previously considered the most important adenosine precursor) and 2) because 2′,3′-cAMP opens mitochondrial permeability transition pores, a pro-apoptotic/pro-necrotic process, conversion of 2′,3′-cAMP to adenosine by the extracellular 2′,3′-cAMP-adenosine pathway would protect tissues by reducing a pro-death factor (2′,3′-cAMP) while increasing a retaliatory metabolite (adenosine)

Cyclic AMP-dependent Protein Kinase Regulates the Alternative Splicing of Tau Exon 10: A MECHANISM INVOLVED IN TAU PATHOLOGY OF ALZHEIMER DISEASE*

Hyperphosphorylation and deposition of tau into neurofibrillary tangles is a hallmark of Alzheimer disease (AD). Alternative splicing of tau exon 10 generates tau isoforms containing three or four microtubule binding repeats (3R-tau and 4R-tau), which are equally expressed in adult human brain. Dysregulation of exon 10 causes neurofibrillary degeneration. Here, we report that cyclic AMP-dependent protein kinase, PKA, phosphorylates splicing factor SRSF1, modulates its binding to tau pre-mRNA, and promotes tau exon 10 inclusion in cultured cells and in vivo in rat brain. PKA-Cα, but not PKA-Cβ, interacts with SRSF1 and elevates SRSF1-mediated tau exon 10 inclusion. In AD brain, the decreased level of PKA-Cα correlates with the increased level of 3R-tau. These findings suggest that a down-regulation of PKA dysregulates the alternative splicing of tau exon 10 and contributes to neurofibrillary degeneration in AD by causing an imbalance in 3R-tau and 4R-tau expression

Review. Activation patterns of microglia and their identification in the human brain

Microglia in the central nervous system are usually maintained in a quiescent state. When activated, they can perform many diverse functions which may be either beneficial or harmful depending on the situation. Although microglial activation may be accompanied by changes in morphology, morphological changes cannot accurately predict the function being undertaken by a microglial cell. Studies of peripheral macrophages and in vitro and animal studies of microglia have resulted in the definition of specific activation states: M1 (classical activation) and M2 (sometimes subdivided into alternative activation and acquired deactivation). Some authors have suggested that these might be an overlapping continuum of functions rather than discrete categories. In this review, we consider translational aspects of our knowledge of microglia: specifically, we discuss the question as to what extent different activation states of microglia exist in the human central nervous system, which tools can be used to identify them and emerging evidence for such changes in ageing and in Alzheimer's disease