Cancer cells can activate the molecular mechanisms of oncogene expression by
Posted Aug 28 2012 6:45am
August 16 2012 News / Bio valley BIOON / - Recently, researchers from the University of South Florida and Moffitt Cancer Center found a molecular mechanisms of cancer cells, can reveal how certain types of cancer cells "hijack" the body's biological response process to activate the growth of cancer cells as well as the expression of oncogenes. Related to study results published in a recent issue of the international magazine Nature Structural & Molecular Biology.
This newly discovered mechanism involving histone class, histone cells in a class of strongly basic protein, can wrap DNA and its sort. Histone H2B in chromatin structure, one of five main histone. Chromatin in eukaryotic cells by DNA and proteins, and which constitutes the nucleus of the eukaryotic cell contents.
The eukaryotic cells can be a variety of mechanisms to maintain the richness of histone at an appropriate level, wherein a mechanism is that the cells, once completed the synthesis of DNA, then histone transcription or synthetic stops, however the cell how to terminate histone the synthesis of the researchers do not know.
The research team found that an histone modification can regulate its own synthesis, this modification is H2B 37 tyrosine phosphorylation, which is very important for the core histone mRNA synthesis inhibition. In additional experiments in mammals and yeast cells, the researchers confirmed their discovery mechanism is widespread and in evolutionary conserved.
When the researchers found that the tyrosine kinase WEE1, cancer occurrence is beginning to emerge. The tyrosine kinases are a group transfer of a phosphate group, and enzymes play switch roles in cell function, which can adjust the critical cellular processes, including cell growth, proliferation and differentiation.
Researchers Mahajan explained, we found WEE1 tyrosine kinase phosphorylation in mammalian cells and yeast cells H2B. WEE1 protein levels in the cell is tightly adjusted, and its role in the cell cycle in a very sturdy. The researchers found that WEE1 is a novel histone H2B regulon can be suppressed H2B, destroy its function, and ultimately lead to the lack of phosphorylation of H2B Tyr, and ultimately increase the transcription of multiple core histone gene.
The data reveal a previously unknown mechanism that is Tyr (tyrosine) phosphorylated histone H2B and functional assessment. The study also reveals WEE1 previously unknown function, can be used as a cell regulator, plays a dual role in maintaining histone transcriptional level.
WEE1 expression increased in glioblastoma and triple negative breast cancer, can reveal the molecular mechanisms of cancer cells by "hijacking" to reduce the levels of histone ultimately activate cancer cell growth and proliferation.