After HIV enters a T-cell, three enzymes play essential roles in the life cycle of the virus. Reverse transcriptase copies the viral RNA genome and makes a DNA copy. Integrase inserts this viral DNA into the cell’s DNA. In the last steps of the viral life cycle, HIV protease cuts HIV proteins into their functional parts.
This animation was created based on atomic structures from the Protein Data Bank: Reverse Transcriptase: 3hvt, 3dlk, 3v6d, 3v4i, 3klg, 3v81 Integrase: 3os1, 3os0, 3oya Protease: 3pj6, 1kj4, 1hxb, 2az9, 2azc HIV Polyprotein, Capsid Protein, Matrix Protein: 1l6n, 2m8l, 1tam
Story: David S. Goodsell
Animation and Video Editing: Maria Voigt
Narration: Brian Hudson
Music: Gosta Berling
The current paradigm of RNA-binding proteins is that they contain regions, or domains, that fold tightly into an ordered interaction platform that mediate RNA binding. In this review, we describe how this paradigm has been challenged by studies showing that other, hitherto neglected regions in RNA-binding proteins, which in spite of being intrinsically disordered, can play key functional roles in protein-RNA interactions. Proteins harbouring such disordered regions are involved in virtually every step of RNA regulation and, in some instances, have been implicated in disease. Based on exciting recent discoveries that indicate their unexpectedly pervasive role in RNA binding, we propose that the systematic study of disordered regions within RNA-binding proteins will shed light on poorly understood aspects of RNA biology and their implications in health and disease.
FULL PAPER HERE
Recently, two independents works published in Nature Com and NSMB have shown the unexpected complexity of the repertoire of RNA-binding proteins in both S. cerevisiae and C. Elegans. Strikingly, metabolic enzymes and other enzymatic cores arise as enigmatic RNA-binders from yeast to human, suggesting either surprising and conserved roles of these proteins in post-transcriptional control of gene expression or a widespread function of RNA as regulator of enzymatic activities.
For more details visit:
The RNA-binding proteomes from yeast to man harbour conserved enigmRBPs.
Benedikt M. Beckmann, Rastislav Horos, Bernd Fischer, Alfredo Castello, Katrin Eichelbaum, Anne-Marie Alleaume, Thomas Schwarzl, Tomaž Curk, Sophia Foehr, Wolfgang Huber, Jeroen Krijgsveld & Matthias W. Hentze
Conserved mRNA-binding proteomes in eukaryotic organisms
Ana M Matia-González, Emma E Laing & André P Gerber
In the past century, few areas of biology advanced as much as our understanding of the pathways of intermediary metabolism. Initially considered unimportant in terms of gene regulation, crucial cellular fate changes, cell differentiation, or malignant transformation are now known to involve ‘metabolic remodeling’ with profound changes in the expression of many metabolic enzyme genes. This review focuses on the recent identification of RNA-binding activity of numerous metabolic enzymes. We discuss possible roles of this unexpected second activity in feedback gene regulation (‘moonlighting’) and/or in the control of enzymatic function. We also consider how metabolism-driven post-translational modifications could regulate enzyme-RNA interactions. Thus, RNA emerges as a new partner of metabolic enzymes with far-reaching possible consequences to be unraveled in the future.
In the last issue of the Biochemist (the journal of the Biochemical society) is focus on RNA. The different reviews, written by leading RNA scientists, give an overview of the function of ribozymes, novel initiation codons and RNA modifications in RNA biology. In addition, this issue provides an comprehensive description of the mechanisms of RNA silencing in plants, the emergent roles of mitochondrial RNAs and chromosome silencing by Xist non-coding RNA. We have contributed to it with a snapshot in our current knowledge in RNA-binding proteins and the news avenues of research that aroused from the HeLa and HEK293 mRNA interactomes (Castello et al., Cell 2012 and Baltz et al., Mol Cell, 2012).
For more information visit: http://www.biochemist.org/bio/