Zebrafish model of human melanoma reveals new cancer gene.

Zebrafish model of human melanoma reveals new cancer gene.

Gene expressionThe act of transcription and, if needed, translation of a gene. Regulation of gene expression is tightly regulated. Genes must only be expressed in the correct cells, at the right time and in the correct amount. Abnormal gene expression is always found in cancer cells. in each individual cell by is controlled by altering the structure of the DNAAbbreviation for deoxyribonucleic acid. Composed of very long strings of nucleotides, which are abbreviated as A, C, G and T. DNA is the storage form of our genetic material. All of the instructions for the production of proteins are encoded in our DNA. .  One major way is altering its degree of coiling; uncoiled DNA is available to be copied into RNAAlso: ribonucleic acid. RNA is a polymer comprised of the nucleotides A, C, G and U. RNA is the working form of our genetic information. RNA is produced via the process of transcription. Some RNA is used to help build ribosomes (rRNA) and some (mRNA) are used to guide the formation of proteins. Other forms of RNA are used to perform specialized functions in the nucleus. but tightly coiled DNA is not. It would be like unwinding string from spool of thread.

BRAF is the most commonly mutated gene in melanoma. Scientists have used zebrafish to observe the impact of this gene on melanoma development, and they have discovered that samples with mutated BRAF genes have more histone methyltransferase, an enzymeA protein that speeds up the process of chemical reactions in the body without becoming altered in the process. Almost every biological process is driven by the activity of enzymes. Without enzyme catalysts, the complex reactions that build and break down cell parts would not happen at a rate compatible with life. Enzyme names usually describe the reaction that is being catalyzed and all of them end in -ase. that adds methyl groups to DNA and causes it to coil more tightly. This discovery identifies the gene that encodes the enzyme, SETDB1, as an oncogeneA defective gene that is involved in triggering cancer cell growth. Oncogenes are altered forms of genes that normally are involved stimulating cell division. These normal genes are mutated and function in an inappropriate manner in cancer cells. An analogy would be that a mutated oncogene is like a car's gas pedal stuck in the on position. All forms of cancer have one or more mutant oncogenes. Examples of oncogenes that are altered in many cancers are myc, ras and Her-2/neu. Contrast with 'tumor suppressor'. directly involved in melanoma development.

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