PACS-2: A key regulator of mitochondria-associated membranes (MAMs)

Chenrui Li1, Li Li1, Ming Yang1

  • 1Department of Nephrology, The Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, Hunan, China.

Insights

Phosphofurin acidic cluster sorting protein 2 (PACS-2) is a key regulator of mitochondria-associated membranes (MAMs), crucial for cellular homeostasis. Understanding PACS-2

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Mitochondria-associated membranes (MAMs) are critical contact sites between mitochondria and the endoplasmic reticulum (ER).
  • MAMs regulate vital cellular processes including calcium signaling, lipid metabolism, mitochondrial function, and autophagy.
  • Dysregulation of MAMs is implicated in various diseases like obesity, diabetes, and neurodegeneration.

Purpose of the Study:

  • To review the current understanding of Phosphofurin acidic cluster sorting protein 2 (PACS-2) as a regulator of MAMs.
  • To present the structure and diverse functions of PACS-2.
  • To explore the link between PACS-2 and disease pathogenesis.

Main Methods:

  • Literature review of existing studies on MAMs and PACS-2.
  • Analysis of PACS-2's role in cellular homeostasis.
  • Examination of PACS-2's involvement in disease mechanisms.

Main Results:

  • PACS-2 is identified as a multifunctional sorting protein localized at MAMs.
  • PACS-2 plays a critical role in maintaining the homeostasis of mitochondria, ER, and lysosomes.
  • PACS-2's functions are intrinsically linked to MAMs' involvement in cellular processes.

Conclusions:

  • PACS-2 is a pivotal regulator of MAMs and cellular homeostasis.
  • The multifaceted roles of PACS-2 highlight its significance in health and disease.
  • PACS-2 represents a potential therapeutic target for treating diseases associated with MAM dysfunction.

Related Concept Videos

Mitochondrial Membranes01:45

Mitochondrial Membranes

A single mitochondrion is a bean-shaped organelle enclosed by a double-membrane system. The outer membrane of mitochondria is smooth and contains many porins - the integral membrane transporters. Porins enable free diffusion of ions and small uncharged molecules through the outer mitochondrial membrane but limit the transport of molecules larger than 5000 Daltons. Further, the outer mitochondrial membrane forms a unique structure called membrane contact sites with other subcellular organelles,...
16.2K
The Inner Mitochondrial Membrane01:28

The Inner Mitochondrial Membrane

The inner mitochondrial membrane is the primary site of ATP synthesis. The inner membrane domain that forms a smooth layer adjacent to the outer membrane is called the inner boundary membrane. This domain contains membrane transporters that drive metabolites in and out of the mitochondria.  In contrast, the inner membrane network that invaginates into the matrix space is called the cristae membrane. This domain accounts for principle mitochondrial function as it accommodates the protein...
4.3K
Translocation of Proteins into the Mitochondria01:19

Translocation of Proteins into the Mitochondria

Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
11.5K
Mitochondrial Precursor Proteins01:39

Mitochondrial Precursor Proteins

Mitochondrial precursors are partially unfolded or loosely folded polypeptide chains. Newly synthesized precursors are inhibited from spontaneously folding into their native conformation by the cytosolic chaperones, heat shock proteins 70 (Hsp70), and mitochondrial import stimulation factors (MSFs). Precursors bound to MSFs are guided to the TOM70-TOM37 receptors, while precursors bound to Hsp70  chaperones are targetted to TOM20-TOM22 receptor complexes.
Most of the mitochondrial...
3.4K
Structure of Porins01:21

Structure of Porins

Mitochondria, chloroplasts, and gram-negative bacteria have transmembrane, beta-barrel proteins called porins to mediate the free diffusion of ions and metabolites across the membrane. Mitochondrial porin precursors contain conserved amino acid sequences called beta signals at their C-terminal. Beta signals have a  motif of PoXGXXHyXHy (Po-Polar, X-Any amino acid, G-Glycine, Hy-LargeHydrophobic), which are crucial for precursor recognition to initiate precursor assembly. Beta-barrel...
3.7K
The Supercomplexes in the Crista Membrane01:41

The Supercomplexes in the Crista Membrane

The mitochondrial cristae membrane is the primary site for the oxidative phosphorylation (OXPHOS) process of energy conversion mediated through respiratory complexes I to V. These complexes have been widely studied for decades, and it has been proven that they form supramolecular structures called respiratory supercomplexes (SC). These higher-order complexes may be crucial in maintaining the biochemical structure and improving the physiological activity of the individual complexes while...
2.8K