Navigation Links
How protein networks stabilize muscle fibers: Same mechanism as for DNA

The same mechanism that stabilises the DNA in the cell nucleus is also important for the structure and function of vertebrate muscle cells. This has been established by RUB-researchers led by Prof. Dr. Wolfgang Linke (Institute of Physiology) in cooperation with American and German colleagues. An enzyme attaches a methyl group to the protein Hsp90, which then forms a complex with the muscle protein titin. When the researchers disrupted this protein network through genetic manipulation in zebrafish the muscle structure partly disintegrated. The scientists have thus shown that methylation also plays a significant role outside the nucleus. They published their results in Genes and Development.

Methylation in the nucleus

Enzymes, called methyltransferases, transfer methyl (CH3) groups to specific sections of the DNA in the nucleus. In this way, they mark active and inactive regions of the genes. However, not only DNA but also nuclear proteins incur methylation, mostly at the amino acid lysine. Methylated lysines on nuclear proteins promote the formation of protein complexes that control, for example, DNA repair and replication. However, methyltransferases are not only found in the nucleus, but also in the cellular fluid (cytoplasm). Yet, it is not well established which proteins they methylate in the cytoplasm and how this methylation may affect function.

Shown for the first time: methylation in the cytoplasm promotes protein complex formation

The researchers first identified an enzyme which is mainly present in the cytoplasm and which methylates the amino acid lysine (Smyd2). Then they searched for interaction partners of the enzyme Smyd2 and found the heat shock protein Hsp90. The scientists went on to show that Smyd2 and methylated Hsp90 form a complex with the muscle protein titin. "Titin is the largest protein in the human body and known primarily for its role as an elastic spring in muscle cells" explains Linke. "Precisely this elastic region of titin is protected by the association with methylated Hsp90."

Titin requires protection by methylated proteins

In skeletal muscle cells of the zebrafish, Linke's team explored what happens when the protection by the methylated heat shock protein is repressed. By genetic manipulation they altered the organism in such a way that it no longer produced the enzyme Smyd2, which blocked the methylation of Hsp90. Without methylated Hsp90, the elastic titin region was unstable and muscle function strongly impaired; the regular muscle structure was partially disrupted.


Contact: Dr. Wolfgang Linke
Ruhr-University Bochum

Related biology news :

1. Photonic crystal biosensors detect protein-DNA interactions
2. Penn biophysicists create new model for protein-cholesterol interactions in brain and muscle tissue
3. Dont forget the vitamin A when working with its carrier protein
4. Saliva proteins could help detection of oral cancer
5. The structure of the Mre11 protein bound to DNA
6. New lab manual focuses on essential methods for purifying and characterizing proteins
7. Proteins in sperm unlock understanding of male infertility says new study
8. Response to immune protein determines pathology of multiple sclerosis
9. Columbia to award 2008 Horwitz Prize to Arthur Horwich & Ulrich Hartl for cellular protein folding
10. Human protein atlas will help pinpoint disease
11. How neuronal activity leads to Alzheimers protein cleavage
Post Your Comments:
(Date:11/12/2015)... 2015  Arxspan has entered into an agreement ... for use of its ArxLab cloud-based suite of ... partnership will support the institute,s efforts to electronically ... information internally and with external collaborators. The ArxLab ... the Institute,s electronic laboratory notebook, compound and assay ...
(Date:11/9/2015)... Nov. 09, 2015 ... of the "Global Law Enforcement Biometrics ... --> ) has announced ... Enforcement Biometrics Market 2015-2019" report to ... Markets ( ) has announced the ...
(Date:10/29/2015)...  The J. Craig Venter Institute (JCVI) policy group ... Biosecurity: Lessons Learned and Options for the Future," which ... Services guidance for synthetic biology providers has worked since ... --> --> Synthetic biology promises great ... pose unique biosecurity threats. It now is easier than ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... India , November 24, 2015 ... a new market research report "Oligonucleotide Synthesis Market by ... Application (PCR, Gene Synthesis, Diagnostic, DNA, RNAi), End-User (Research, ... 2020", published by MarketsandMarkets, the market is expected to ... Million in 2015, at a CAGR of 10.1% during ...
(Date:11/24/2015)... 2015  Tikcro Technologies Ltd. (OTCQB: TIKRF) today announced that its Annual ... 11:00 a.m. Israel time, at the law offices ... Street, 36 th Floor, Tel Aviv, Israel . ... and Izhak Tamir to the Board of Directors; , ... , approval of an amendment to certain terms of options granted ...
(Date:11/24/2015)... ... November 24, 2015 , ... ... Technologies, Inc., on being named to Deloitte's 2015 Technology Fast 500 list of ... OrthoAccel manufactures AcceleDent®, a FDA-cleared, Class II medical device that speeds up orthodontic ...
(Date:11/24/2015)... , November 24, 2015 , ... a European healthcare fund ... companies will work closely together in identifying European breakthrough technologies ... need. The collaboration is underpinned by a significant investment by ... is the first investment by Bristol-Myers Squibb in a European ...
Breaking Biology Technology: