Question

How does the nucleus coordinate gene expression

Answer 1

Gene regulation is the process of controlling which genes in a cell's DNA are expressed and then making of proteins take place.Gene expression involves many steps, and gene regulation can occur at any of these steps. However, many genes are regulated primarily at the level of transcription, that is in nucleus.
Eukaryotic gene regulation takes place during transcription and RNA processing that takes place in nucleus.
a)Chromatin accessibility. The structure of chromatin can be regulated. More “relaxed” chromatin makes a gene more available for transcription.
b)Transcription. Transcription is a key regulatory point for many genes. Sets of transcription factor proteins bind to specific DNA sequences in or near a gene and promote or repress its transcription into an RNA.
c)RNA processing. Splicing, capping, and addition of a poly-A tail to an RNA molecule can be regulated inside nucleus.
eukaryotes have evolved mechanisms to recognize abnormal messenger RNAs and prevent them from producing faulty proteins. Protein‐encoding genes are transcribed in the nucleus by RNA polymerase II as precursor RNAs that undergo extensive processing before being translocated to the cytoplasm.
SO, We can say :This spatial and temporal separation between RNA and protein synthesis offers an immense opportunity for control and regulation of gene expression that is all coordinated by nucleus.