Question

. What is an mRNA?

2. How does the RT-PCR tell you if a gene is expressed in a particular cell type?

3. Where can RNases be found? How can you prevent RNase contamination in your samples during experiments involving RNA?

Answer 1

1) Messenger RNA (mRNA) is a large family of RNA molecules, which transmit genetic information from DNA to the ribosome, at this place they specify the amino acid sequence of the protein products of gene expression. Messenger RNA molecule in cells, which carries codes from the DNA in the nucleus to the sites for the synthesis of protein in the cytoplasm. Each molecule of mRNA encodes the information for one protein with each sequence of three nitrogen-containing bases in the mRNA and specify the assimilation of a particular amino acid within the protein. These molecules are transported from the nuclear envelope into the cytoplasm, where they are translated by the rRNA of ribosomes. mRNA genetic information is in the sequence of nucleotides and they are arranged into codons, which consist of three base pairs each. Each codon encodes for a specific amino acid, except the stop codons, which terminate the synthesis of protein. This process of translation of codons into amino acids needs two other types of RNA such as Transfer RNA (tRNA), which mediates detection of the codon and provides the matching amino acid and ribosomal RNA (rRNA), that is the central element of the ribosome's which helps in the formation of protein. The mRNA molecule starts with transcription and ends in degradation. mRNA molecule is processed, edited and transported former to the process of translation. Eukaryotic mRNA molecules need extensive processing and transport, while prokaryotic mRNA molecules do not.