How does HIV enter white blood cells?
Table of Contents
- 1 How does HIV enter white blood cells?
- 2 How does the HIV virus enter the cell?
- 3 How does HIV enter the nucleus?
- 4 How do enveloped viruses differ from Nonenveloped viruses?
- 5 Is DNA ever found in the cytoplasm?
- 6 How do enveloped viruses enter a host cell?
- 7 Where ribosomes are attached to?
- 8 How does a virus envelope form?
How does HIV enter white blood cells?
HIV infects a type of white blood cell in the body’s immune system called a T-helper cell (also called a CD4 cell). These vital cells keep us healthy by fighting off infections and diseases. HIV cannot reproduce on its own. Instead, the virus attaches itself to a T-helper cell and fuses with it (joins together).
How does the HIV virus enter the cell?
When HIV makes contact with a CD4 cell, the gp120 spikes on the surface of HIV lock onto the CD4 receptor and another co-receptor, either CCR5 or CXCR4. The gp41 protein is used to fuse the HIV envelope with the cell wall. This process of fusion allows the HIV capsid to enter the CD4 cell.
How does HIV enter the nucleus?
Based on studies with HIV and other viruses replicating in the nucleus, it seems reasonable to postulate that the HIV-1 PIC is delivered to the nuclear envelope along the microtubule network and enters the nucleoplasm through the nuclear pore.
Which cell surface protein does HIV use to enter cells?
Cell surface receptors for HIV entry into cells. HIV interacts with CD4 and a seven transmembrane (7TM) co-receptor to trigger entry into cells. The envelope glycoprotein spikes on the surface of virus particles comprise an outer surface gp120 (SU) non-covalently linked to a transmembrane gp41 (TM).
Is there reverse transcriptase in the cytoplasm?
The process of reverse transcription generates, in the cytoplasm, a linear DNA duplex via an intricate series of steps. This DNA is colinear with its RNA template, but it contains terminal duplications known as the long terminal repeats (LTRs) that are not present in viral RNA (Fig. 1).
How do enveloped viruses differ from Nonenveloped viruses?
These differences reflect different mechanisms of cell entry and different pathways of assembly and maturation. Enveloped viruses enter by membrane fusion, either from an internal compartment following an endocytic step, or at the cell surface. Non-enveloped viruses require some form of membrane “perforation”.
Is DNA ever found in the cytoplasm?
All of the genetic information in a cell was initially thought to be confined to the DNA in the chromosomes of the cell nucleus. It is now known that small circular chromosomes, called extranuclear, or cytoplasmic, DNA, are located in two types of organelles found in the cytoplasm of the cell.
How do enveloped viruses enter a host cell?
Enveloped animal viruses enter their host cells by a process of membrane fusion. This fusion can occur at the cell plasma membrane or within the endocytic vacuolar system, depending on the characteristics of the virus fusion protein. Examples of both pathways of viral entry are detailed in this review.
Where does the envelope of a virus come from?
A virus that has an outer wrapping or envelope. This envelope comes from the infected cell, or host, in a process called “budding off.” During the budding process, newly formed virus particles become “enveloped” or wrapped in an outer coat that is made from a small piece of the cell’s plasma membrane.
Can RNA be found in the cytoplasm?
DNA is found mostly in the cell nucleus, but another type of nucleic acid, RNA, is common in the cytoplasm.
Where ribosomes are attached to?
rough endoplasmic reticulum
The ribosome that is synthesizing the protein is directly attached to the ER membrane. These membrane-bound ribosomes coat the surface of the ER, creating regions termed rough endoplasmic reticulum, or rough ER (Figure 12-36A).