Viral infection- Human immunodeficiency virus

Structure of Human-Immunodeficiency Disease Virus

HIV is named as a retrovirus because it works in a back-to-front way. Unlike other viruses, using RNA rather than DNA, retroviruses store their genetic information when they enter a human cell in order to form new copies of themselves.

HIV is a spherical virus. The outer shell of the virus is called the envelope and this is often covered in spikes of the ‘glycoproteins’ gp120 and gp41, which permit HIV to lock onto the CD4 receptor on CD4 T cells and enter the cell.

Matrix is a layer  Inside the virus envelope. The core of the virus, or nucleus, is held within the capsid, a cone-shaped structure within the center of the virion. The capsid contains two enzymes necessary for HIV replication, the reverse transcriptase and integrase molecules. It also contains two strands of RNA.

HIV’s RNA is made up of nine genes that contain all the guidance to form new viruses. Three of those genes are – gag, pol, and env – provide the instructions to form proteins that will form new virus particles. Such as, env provides the code to form the proteins that form the envelope, or shell, of HIV. Gag generates structural proteins like the matrix and the capsid, and pol generates the enzymes that are important for making new viruses.

The other six genes referred to as rev, tat, nef, vif, vpr and vpu, provide code to form proteins that control the capacity of HIV to infect a cell, generate new copies of the virus, or release viruses from infected cells.