It is a very excellent animation which explains the hiv replication very clearly. For free download of this video please visit my webpage rufusrajadurai.wetpaint.com And other 3D animation videos visit rufusrajadurai.wetpaint.com Regards, Dr.Rufus The Lyrics of this video is here Targeting HIV replication The replication of HIV 1 is a multi-stage process. Each step is crucial to successful replication and is therefore a potential target of antiretroviral drugs. Step one is the infection of a suitable host-cell, such as a CD4-positive T-lymphocyte. Entry of HIV into the cell requires the presence of certain receptors on the cell surface, CD4 — receptors and co-receptors such as CCR5 or CXCR4. These receptors interact with protein-complexes, which are embedded in the viral envelope. These complexes are composed of two glycoproteins: an extracellular gp 120 and a transmembrane gp 41 When HIV approaches the target cell gp120 binds to the CD4-receptors. This process is termed attachment. It promotes further binding to a co-receptor. Co-receptor binding results in a conformational change in gp120. This allows gp41 to unfold and insert its hydrophobic terminus into the cell membrane. Gp 41 then folds back on itself. This draws the virus towards the cell and facilitates the fusion of their membranes. The viral nucleocapsid enters the host cell and breaks open releasing two viral RNA-strands and 3 essential replication enzymes: Integrase, Protease and Reverse Transcriptase …