Mitochondrial fusion and fission are mediated by a set of GTPase enzymes:

Mitochondrial fusion -MFN1/2 & OPA1

Mitochondrial fission- DRP1

TLS Online TPP Program

#Id: 6801

#Unit 3. Fundamental Processes

Binding of RISC complexes causes the bound mRNPs to associate with P bodies. Since P bodies are major sites of mRNA degradation where the decapping complex DPC1/DPC2, t5′→3′ exonuclease XRN1, and cytoplasmic exosomes are concentrated, mRNAs bound by several RISC complexes are degraded.

TLS Online TPP Program

#Id: 6802

#Unit 3. Fundamental Processes

TLS Online TPP Program

#Id: 6803

#Unit 3. Fundamental Processes

The base pairing between miRNA and target RNA is initiated by interactions of so-called seed residues—typically the sequence between bases 2 and 9 of the 22-nucleotide miRNA

TLS Online TPP Program

#Id: 6804

#Unit 3. Fundamental Processes

Humans express four Argonaute proteins. AGO2 is the human Argonaute protein in miRNA-containing RISC complexes.

TLS Online TPP Program

#Id: 6805

#Unit 3. Fundamental Processes

AGO2 is the protein responsible for the cleavage of targetRNA. One domain of the protein is homologous to theRNase H enzymes that degrade the RNA of an RNA-DNA

hybrid

TLS Online TPP Program

#Id: 6806

#Unit 3. Fundamental Processes

When the 5′ end of the siRNA of a RISC complex base-pairs precisely with a target mRNA over a distance of one turn of an RNA helix (10–12 base pairs), this domain of AGO2 cleaves the phosphodiester bond of the target RNA across from nucleotides 10 and 11 of the siRNA