Navigation Links
Evolution with a restricted number of genes
Date:12/14/2007

The development of higher forms of life would appear to have been influenced by RNA polymerase II. This enzyme transcribes the information coded by genes from DNA into messenger-RNA (mRNA), which in turn is the basis for the production of proteins. RNA polymerase II is highly conserved through evolution, with many of its structural characteristics being conserved between bacteria and humans.

Single-cell organisms were already in existence 500 million years ago, with several thousand genes providing different cellular functions. Further developments seemed dependent on producing even more genes. For a highly developed organism like a human, this form of evolution would have resulted in several million genes. Researchers were therefore surprised to learn, following publication of the human genome, that a human only has around 25,000 genes not many more than a fruit fly or a worm with approximately 15,000 to 20,000 genes. It would appear that, over the last 500 million years, other ways to produce highly complex organisms have evolved. Evolution has simply found more efficient ways to use the genes already there. But what could have made this possible"

In the current issue of Science the group of Prof. Dirk Eick at the Institute of Clinical Molecular Biology and Tumor Genetics, GSF National Research Center for Environment and Health, Munich, and the group of Dr. Shona Murphy from Oxford University, England, publish results which represent a piece of the puzzle and shed new light on to the purpose of an unusual structure in RNA polymerase II. They build on earlier observations that gene expression is not just regulated by binding of the enzyme to the gene locus to which it is recruited, but also during the phase of active transcription from DNA into RNA. During this phase, parts of the newly synthesised RNA may be removed and the remaining sequences combined into new RNA message. This splicing of RNA occurs during gene transcription, and in extreme cases, can produce RNAs coding for several thousand different proteins from a single gene.

But what was the development that permitted this advance in gene usage" The RNA polymerase II has developed a structure composed of repeats of a 7 amino-acid sequence. In humans this structure termed carboxyterminal domain or CTD is composed of 52 such repeats. It is placed exactly at the position where RNA emerges from RNA polymerase II. In less complex organisms the CTD is much shorter: a worm has 36 repeats, and yeast as few as 26, but many single-cell organisms and bacteria have never developed an obvious CTD structure.

Although the requirement of CTD for the expression of cellular genes in higher organisms is undisputed, the molecular details for the gene-specific maturation of RNAs is still largely enigmatic. The groups of Dirk Eick and Shona Murphy have now shown a differential requirement for phosphorylation of the amino acid serine at position 7 of CTD in the processing and maturation of specific gene products. These results provide the groundwork for the discovery of further pieces of the CTD puzzle and thus enlarge our knowledge of gene regulation. Given its fundamental importance, understanding the mechanism of gene regulation is essential if we are to understand cancer and other diseases at the molecular level and develop new therapies.


'/>"/>

Contact: Professor Dr. Dirk Eick
eick@gsf.de
49-089-709-9512
GSF - National Research Center for Environment and Health
Source:Eurekalert

Related biology news :

1. Evolution is driven by gene regulation
2. Clones on task serve greater good, evolutionary study shows
3. Adaptation to parasites drive African fishes along different evolutionary paths
4. Uncertainty drives the evolution of cooperative breeding in birds
5. Structure of 450 million year old protein reveals evolutions steps
6. Scientists retrace evolution with first atomic structure of an ancient protein
7. Hidden interactions between predators and prey: evolution causes cryptic dynamics in ecology
8. Migrating squid drove evolution of sonar in whales and dolphins, researchers argue
9. Old developmental pathways spawn revolutionary evolutionary changes
10. Systems Biology poised to revolutionize the understanding of cell function and disease
11. Using evolution, UW team creates a template for many new therapeutic agents
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/20/2016)... 2016  VoiceIt is excited to announce its ... By working together, VoiceIt and VoicePass will ... VoicePass take slightly different approaches to voice biometrics, ... and usability. ... partnership. "This marketing and technology partnership ...
(Date:5/3/2016)... May 3, 2016  Neurotechnology, a provider of ... MegaMatcher Automated Biometric Identification System (ABIS) , a ... projects. MegaMatcher ABIS can process multiple complex biometric ... combination of fingerprint, face or iris biometrics. It ... and MegaMatcher Accelerator , which have ...
(Date:4/26/2016)... April 27, 2016 Research ... Multi-modal Biometrics Market 2016-2020"  report to their offering.  ... The analysts forecast the global multimodal ... 15.49% during the period 2016-2020.  Multimodal ... sectors such as the healthcare, BFSI, transportation, automotive, ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... ... June 27, 2016 , ... Rolf K. Hoffmann, ... faculty of the University of North Carolina Kenan-Flagler Business School effective ... at UNC Kenan-Flagler, with a focus on the school’s international efforts, leading classes ...
(Date:6/24/2016)... June 24, 2016  Regular discussions on a range of ... between the two entities said Poloz. Speaking at ... Ottawa , he pointed to the country,s inflation target, ... government. "In certain ... institutions have common economic goals, why not sit down and ...
(Date:6/24/2016)... ... June 24, 2016 , ... Researchers at the Universita Politecnica delle Marche in ... peritoneal or pleural mesothelioma. Their findings are the subject of a new article on ... biomarkers are signposts in the blood, lung fluid or tissue of mesothelioma patients that ...
(Date:6/23/2016)... CAMBRIDGE, Mass. , June 23, 2016 /PRNewswire/ ... the development of novel compounds designed to target ... compound, napabucasin, has been granted Orphan Drug Designation ... in the treatment of gastric cancer, including gastroesophageal ... cancer stemness inhibitor designed to inhibit cancer stemness ...
Breaking Biology Technology: