Different types of RNAs and the central dogma of biology explained
When we hear RNAs many of us think about it as some cell organelles that produce proteins. Or perhaps, some people do not know what an RNA is. Its main function is to produce proteins; however, it has many functions. But how does a small RNA translate proteins which are essential for the survival of the humans? These RNAs are always neglected and they deserve some attention for the enormous work they do.
So let us begin with the “Central Dogma of Biology”. Many biology students dread it; however, it is an important concept we should understand. It all begins with our good old friend DNA. In my opinion, it is the king in our bodies. It contains our genes! So the DNA in the nucleus of the cell to be specific in the nucleolus transcribes an mRNA or the messenger RNA. To transcribe an mRNA the DNA initially has to replicate itself. To transcribe means to copy a DNA strand to produce RNA and this is the first step in gene expression. The DNA has two complementary strands that are separated by the enzyme helicase. The enzyme polymerase starts to add complementary bases to the strands. The newly created DNA is “Rezipped” by the enzyme ligase. In order for the DNA to be expressed, this information needs to be taken out of the nucleus. Therefore, a messenger RNA is transcribed. The process is somewhat similar to the DNA Replication, however, the thymine base changes to the uracil base. This messenger RNA goes out of the cell and binds to the rRNA which is a site of protein translation. Another type of ribosome helps in this process; which is the tRNA.The tRNA or transfer binds to the mRNA codons which are complementary to its anticodons. Codons are a sequence of three nucleotides that define the genetic code. There are properties associated with codons and single mutations can cause pathologies for example anemia. Transfer RNA connects the mRNA and the amino acids which form the proteins. The cycle goes on until the stop codon enters and cease it. A newly nonfunctional protein is formed. It needs folding to be fully functional. Remember structure determines function in biology! These are the types of RNAs essential for protein formation.
RNAi short for RNA interference is another type of protein which regulates the expression of the genes by binding to the mRNAs and as structure determines function no more protein translation can occur. This is very useful when the cell wants to preserve energy which is consumed excessively when proteins are translated. Studies about RNAi indicate that RNAi could target diseases. This study is in phase II which means it can be helpful in the near future!
Works Cited:
Comments
Post a Comment