When cellular iron concentrations return to normal levels, IRP1 is converted to aconitase, and IRP2 undergoes proteolytic degradation, ending the low-iron response.

TLS Online TPP Program

#Id: 7913

#XL - Q Biochemistry

Matrix-targeting sequences

sequences for localizing proteins to mitochondria

TLS Online TPP Program

#Id: 7912

#XL - Q Biochemistry

The majority of proteins located in mitochondria are not encoded by mtDNA, they are encoded by genes in the nucleus and are imported into the mitochondria after their synthesis in the cytosol.

TLS Online TPP Program

#Id: 7911

#XL - Q Biochemistry

MCSs also serve as interfaces for the transfer of ions (Ca+2 ) and small molecules (glycerophospholipids) between the ER and mitochondria.

TLS Online TPP Program

#Id: 7910

#XL - Q Biochemistry

Mitochondria-associated membranes (MAMs)

The portions of the ER membranes that form special contact regions with the mitochondria.

TLS Online TPP Program

#Id: 7909

#XL - Q Biochemistry

Membrane contact sites (MCSs)

Mitochondria establish MCSs with many other organelles, including ER, lysosomes, peroxisomes, the plasma membrane, the Golgi, endosomes, and even lipid droplets.

TLS Online TPP Program

#Id: 7908

#XL - Q Biochemistry

In healthy mitochondria, PINK1 resides in the mitochondrial matrix.

In damaged or dysfunctional mitochondria, PINK1 resides on the outer mitochondrial membrane, where it recruits cytosolic Parkin.