Gene expression occurs in two stages.
1) Transcription refers to the synthesis of RNA molecule on a DNA template. The process is carried out by DNA-dependent RNA polymerase.
2) Translation: The RNA sequence (mRNA) is converted into amino acid sequence corresponding to a protein.
During the transcription three types of RNA could be produced. All the three RNAs are involved in the translation process. The RNAs are
a) messenger RNA (mRNA)
b) transfer RNA (tRNA)
c) ribosomal RNA (rRNA)
The strand of DNA that acts as the template during transcription is template strand or antisense strand. The other strand is called the coding strand or sense strand. The sequence of coding DNA strand is the same as that of the mRNA sequence except that it possess T instead of U.
A new class of RNA molecules referred to as ultraconserved non-coding RNAs (UCRs), previously considered “junk”, are now shown to be involved in cancer development. These UCRs might prove useful in disease diagnosis, and determining a patient’s prognosis and treatment. Here is the report.