Editorials |
From the Department of Physiology, University of Wisconsin Medical School.
Correspondence to Héctor H. Valdivia, MD, PhD, Department of Physiology, University of Wisconsin Medical School, 601 Science Dr. Madison, WI 53711. E-mail valdivia@physiology.wisc.edu
See related article, pages 874883
Key Words: ryanodine receptor alternative splicing excitation-contraction coupling apoptosis
An extract of the first 250 words of the full text is provided, because this article has no abstract. |
When the human genome sequence was first drafted in 2000, researchers were shocked by the low number of genes found. Humans make
90 000 different types of protein, so estimates were that at least a similar number of genes would be found. The logic was that, given the structural and functional complexity of the human body, we ought to have more genes than the simpler corn (zea mays,
40 000 genes) or the puny worm Caenorhabditis elegans (
19 500 genes). So, when the final number of human genes was established to be fewer than 25 000, researchers immediately realized the gene:protein mismatch, reaffirmed the notion that the axiom "one gene, one protein" was inaccurate, and began looking for the evolutionary mechanisms that increase diversity and complexity from a relatively simple genetic makeup. The answer, it seems, is alternative gene splicing.
When a segment of DNA (gene) is transcribed, the resulting RNA (tRNA) contains meaningful (exons) and nonmeaningful (introns) sequences that must be edited to produce a coherent message (mRNA). This cut-and-paste process where exons are retained and introns are discarded is called gene splicing and constitutes the normal processing of genes. However, as it was first discovered some 25 years ago,1 "alternative splicing" occurs, a highly regulated process that confers sophistication to the manufacturing of proteins by frequently "violating the rules" and leaving pieces of introns or excising parts of exons in the final mRNA. The resultant protein, a splice variant, thus contains segment(s) of distinct amino
Related Article:
Circ. Res. 2007 100: 874-883.
This article has been cited by other articles:
![]() |
V. Srivastava, M. K. Srivastava, K. Chibani, R. Nilsson, N. Rouhier, M. Melzer, and G. Wingsle Alternative Splicing Studies of the Reactive Oxygen Species Gene Network in Populus Reveal Two Isoforms of High-Isoelectric-Point Superoxide Dismutase Plant Physiology, April 1, 2009; 149(4): 1848 - 1859. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Eisenreich, V. Y. Bogdanov, A. Zakrzewicz, A. Pries, S. Antoniak, W. Poller, H.-P. Schultheiss, and U. Rauch Cdc2-Like Kinases and DNA Topoisomerase I Regulate Alternative Splicing of Tissue Factor in Human Endothelial Cells Circ. Res., March 13, 2009; 104(5): 589 - 599. [Abstract] [Full Text] [PDF] |
||||
|
Circulation Research Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2007 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |