Nucleus

nucleoplasm

The part of the nucleus that is a gel-like substance, it’s the cytoplasm (that’s for the cell) of the nucleus

FC

the region of the nucleolus where the rRNA synthesis begins

• lightest part of the nucleolus

DFC

the region of the nucleolus that surrounds the FC

• rRNA processing and cleavage occurs here

granular component

region of the nucleolus that is outside of the FC and DFC, where the ribosomal subunit assembly occurs

40

Small molecules of the size less than _ kDa can slip through the nuclear membrane easily

simple, facilitated

Molecules that are less than 40 kDa go through __ or _ diffusion

chromatin

histones with DNA wrapped around

chromatin

In the nucleus, DNA isn’t just floating around, it is available in the form of ___

nuclear lamina

What is the name of the cytoskeleton of the nucleus?

dimer

One lamina protein combines with another to form a ___

lamina

Multiple dimers weave to form a long filament, and these filaments weave together to form a network called the __

nuclear envelope

The double membrane around the nucleus is called the:

lamina

This structure:

• Gives the nucleus its shape

• Holds the nuclear membrane in place

• Helps anchor chromatin (the DNA structure) to the nuclear envelope

LBR and Emerin

What are the two proteins in the inner nuclear membrane that attach the inner nuclear membrane to the lamina sitting right below it?

lamin B

LBR binds to _ _ (type of lamin protein) that helps it attach to the inner membrane

outer

Does the KASH protein sit in the inner or outer nuclear membrane?

inner

Does the SUN protein sit in the inner or outer nuclear membrane?

LINC

What is the name of the complex that is made when SUN and KASH proteins connect?

cytoskeleton

What do KASH proteins connect to in the cytoplasm?

NLS

Proteins that are meant to be sent to the nucleus have the signal sequence called: 

lysine and arginine

What residues are the NLS composed of?

7

How many amino acids long is the NLS?

importin

An ___ is a chaperone that binds to the NLS to bring the protein into the nucleus

FG

The importin interacts with the __-nucleoporins on the nuclear pore complex, which forms a mesh that controls what enters the nucleus

Ran-GTP

_-_ binds to the importin, causing the importin to drop the cargo

against

The importin is going with/against the gradient when it exits the nuclear pore

GTP

The __ helps to move the importin against the gradient

Ran-GAP

Once Ran-GTP + importin exits the nucleus, the GTP is converted back to GDP + Pi by the ___, causing the Ran-GTP to release the importin

exportin-T

Which exportin binds to tRNA?

exportin-5

Which exportin binds to miRNA?

Crm1

Which exportin binds to rRNA?

none, RNA helicase

Which exportin binds to mRNA?