Replication cycle Entry to the cell HIV enters macrophages and CD4 T cells by the adsorption of glycoproteins on its surface to receptors on the target cell followed by fusion of the viral envelope with the cell membrane and the release of the HIV capsid into the cell.

Cell compartmentalization The nuclear envelope allows the nucleus to control its contents, and separate them from the rest of the cytoplasm where necessary.

Stretch the envelope.

Entry to the cell begins through interaction of the trimeric envelope complex (gp160 spike) and both CD4 and a chemokine receptor (generally either CCR5 or CXCR4, but others are known to interact) on the cell surface.

If the nuclear envelope has broken down, a new nuclear envelope forms using the membrane vesicles of the parent cell's old nuclear envelope.

I need an envelope.

Tom sealed the envelope.

What's in the envelope?

Tom opened the envelope.

This is, in turn, surrounded by the viral envelope that is composed of two layers of fatty molecules called phospholipids taken from the membrane of a human cell when a newly formed virus particle buds from the cell.

An example is HIV, which mutates rapidly, so the proteins on its viral envelope that are essential for entry into its host target cell are constantly changing.

The nuclear envelope breaks down.

He cut the envelope open.

Do you need an envelope?

Do you need an envelope?

Please give me an envelope.

I handed Tom the envelope.

What was in the envelope?

Each kind used a thin gastight metal envelope, rather than the usual rubber coated fabric envelope.

Embedded in the viral envelope are proteins from the host cell and about 70 copies of a complex HIV protein that protrudes through the surface of the virus particle.

An envelope and a stamp, please.

The letter is inside the envelope.

Tom handed Mary a large envelope.

She gave me a sealed envelope.

He handed her a sealed envelope.

They had to fit within the envelope.

Tom put the envelope on the table.

Tom put an envelope on Mary's desk.

Are you going to open the envelope?

Aren't you going to open the envelope?

Tom handed a small envelope to Mary.

X Planes Pushing the Envelope of Flight .

Envelope The envelope itself is the outer surface, usually surrounding one or more gas bags and or ballonets within it.

Nuclear Envelope and Nuclear Import Section from Landmark Papers in Cell Biology, Joseph G. Gall, J. Richard McIntosh, eds., contains digitized commentaries and links to seminal research papers on the nucleus.

Write your name and address on this envelope.

He opened the envelope only to be disappointed.

I wrote the wrong address on the envelope.

The secretary put the letter into the envelope.

All the time, you have been given an envelope.

I forgot to write the address on the envelope.

I've written his address on the back of the envelope.

In HIV, the envelope that covers the virion is formed from the outermost membrane of the host cell such self cloaked viruses make it difficult for the immune system to identify them as non self structures.

Cell.

Cell junction molecules The molecules responsible for creating cell junctions include various cell adhesion molecules.

Once inside the cell, the acidic conditions in the endosome cause two events to happen First, part of the hemagglutinin protein fuses the viral envelope with the vacuole's membrane, then the M2 ion channel allows protons to move through the viral envelope and acidify the core of the virus, which causes the core to disassemble and release the viral RNA and core proteins.