Lucy L. answered • 01/21/21
Lucy (CA certified multiple subject teacher K-5)
I will try my best to explain the connection through the points below:
Beta cells are a type of cell found in pancreatic islets (These are groups of cells found within the pancreas that release hormones). The primary function of a beta cell is to produce and release insulin and amylin.
Both insulin and amylin are hormones that reduce blood glucose levels. So when a person's blood glucose spikes, beta cells can react quickly and release stored insulin and amylin while simultaneously producing more.
The production of insulin in the beta cell is where you see connections with proteins and DNA.
First of all, beta cells are the only site where insulin is produced in mammals. When glucose causes insulin secretion it also promotes insulin biosynthesis (new production of insulin). This biosynthesis is done through translation control/regulation (this refers to the controls of the levels of protein synthesized by mRNA).
The insulin gene is first transcribed into the mRNA (transcription is the process by which the information in a strand of DNA is copied into a new molecule of messenger RNA (mRNA). After transcription, it is translated into preproinsulin (biologically inactive precursor to the biologically active hormone insulin).
Then, the signal peptidases (enzymes that convert secretory and some membrane proteins to their mature or pro-forms by cleaving their signal peptides from their N-termini) cleaves the preproinsulin and forms it into proinsulin. (This all happens in the rough endoplasmic reticulum)
The proinsulin is then transported to the Golgi apparatus is once again cleaved to form insulin and c-peptide.
Insulin is a 51 amino acid protein! (Insulin is encoded as a 110 amino acid precursor but is released/secreted as a 51 amino acid protein.
Summary: DNA is essential to the production of insulin by beta cells (since beta cells use mRNA to create/produce molecules that lead to the creation of insulin; insulin is a protein!
Hope this helps! Feel free to reach out/message me for clarification/further assistance!
