In a step toward deciphering the “splicing code” of the human genome, researchers at the University of California, San Diego School of Medicine have comprehensively analyzed six of the more highly expressed RNA binding proteins collectively known as heterogeneous nuclear ribonucleoparticle (hnRNP) proteins.
UC San Diego School of Medicine
RNAs wound in a knot and bound by hnRNP proteins illustrates the intractable problem of RNA regulation addressed by Huelga et al.
This study, published online Feb 16 in Cell Press’ new open-access journal Cell Reports, describes how multiple RNA binding proteins cooperatively control the diversity of proteins in human cells by regulating the alternative splicing of thousands of genes.
In the splicing process, fragments that do not typically code for protein, called introns, are removed from gene transcripts, and the remaining sequences, called exons, are reconnected. The proteins that bind to RNA are important for the control of the splicing process, and the location where they bind dictates which pieces of the RNA are included or excluded in the final gene transcript -- in much the same fashion that removing and inserting scenes, or splicing, can alter the plot of a movie.
“By integrating vast amounts of information about these key binding proteins, and making this data widely available, we hope to provide a foundation for building predictive models for splicing and future studies in other cell types such as embryonic stem cells,” said principal investigator Gene Yeo, PhD, assistant professor in the Department of Cellular and Molecular Medicine and the Institute for Genomic Medicine at UC San Diego, and a visiting professor at the Molecular Engineering Laboratory in Singapore. “If we can understand how these proteins work together and affect one another to regulate alternative splicing, it may offer important clues for rational drug design.”
The data sets highlighted in this study – derived from genome-wide methods including custom-designed splicing-sensitive microarrays, RNA sequencing and high-throughput sequencing to identify genome-wide binding sites (CLIP-seq) -- map the functional binding sites for six of the major hnRNP proteins in human cells.
“We identified thousands of binding sites and altered splicing events for these hnRNP proteins and discovered that, surprisingly these proteins bind and regulate each other and a whole network of other RNA binding proteins, suggesting that these proteins are important for the homeostasis of the cell,” said first author, NSF fellow Stephanie C. Huelga.
According to the UCSD researchers, the genes specifically targeted by the RNA binding proteins in this study are also often implicated in cancer. Yeo added that of the thousands of genomic mutations that appear in cancer, a vast majority occur in the introns that are removed during splicing; however, intronic regions are where regulatory hnRNP proteins often bind.
“Our findings show an unprecedented degree of complexity and compensatory relationships among hnRNP proteins and their splicing targets that likely confer robustness to cells. The orchestration of RNA binding proteins is not only important for the homeostasis of the cell, but – by mapping the location of binding sites and all the regulatory places in a gene – this study could reveal how disruption of the process leads to disease and, perhaps, a way to intervene.”
Additional contributors to the study include Anthony Q. Vu, Justin D. Arnold, Tiffany Y. Liang, Patrick P. Liu and Bernice Y. Yan, UCSD Cellular and Molecular Medicine; John Paul Donohue, Lily Shiue and Manuel Ares, Jr., UC Santa Cruz; Shawn Hoon and Sydney Brenner, A*STAR, Singapore.
The study was funded in part by grants from the National Institutes of Health and the UC San Diego Stem Cell Research Program.
Debra Kain | Newswise Science News
Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute
Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy