ANXA7 - Annexin A7 | Elisa - Clia - Antibody - Protein

Background:

Annexin A7, also known as ANXA7, is a protein encoded by the ANXA7 gene in humans. It belongs to the annexin family of calcium-dependent phospholipid-binding proteins. Annexin A7 is a relatively large protein, consisting of about 505 amino acids with a molecular weight of approximately 53 kDa. Like other annexins, Annexin A7 binds to phospholipids in a calcium-dependent manner. It has a preference for phosphatidylinositol phospholipids. Annexin A7 is found in various cellular compartments, including the cytoplasm, nucleus, and plasma membrane. Its localization can be influenced by cellular conditions and stimuli. Annexin A7 has been implicated in the regulation of cellular calcium signaling. It can interact with components of calcium signaling pathways, including inositol 1,4,5-trisphosphate receptors (IP3Rs), which are involved in releasing calcium from intracellular stores. Annexin A7 has been suggested to act as a tumor suppressor in certain contexts. It may regulate cell growth, proliferation, and apoptosis. Reduced expression of ANXA7 has been associated with various cancers. Annexin A7 is involved in endocytosis and vesicle trafficking within cells. It plays a role in the formation and trafficking of endosomes, which are vesicles that transport molecules within the cell. Annexin A7 has been proposed to play a role in membrane repair mechanisms in cells. It may participate in the resealing of damaged membranes. Annexin A7 has been linked to lipid metabolism, particularly in adipocytes. It may influence lipid droplet formation and adipogenesis.

Protein Structure:

• Core Domain: ANXA7 consists of four annexin repeats, which are the typical structural motifs for annexins. These repeats allow ANXA7 to bind calcium and interact with phospholipid membranes.
• N-terminal Domain: The N-terminal domain of ANXA7 is unique and essential for its interaction with other proteins and cellular components.
• C-terminal Domain: The C-terminal domain also contributes to membrane binding and interaction with other proteins.

Classification and Subtypes:

ANXA7 is classified within the annexin family, which includes other members such as ANXA1 through ANXA13. It does not have specific subtypes, but its function can vary depending on cellular context and calcium concentration.

Function and Biological Significance:

• Membrane Dynamics: ANXA7 is crucial in processes involving membrane fusion, exocytosis, and endocytosis. It helps regulate vesicle trafficking and membrane repair.
• Calcium Signaling: By binding to calcium ions, ANXA7 influences intracellular calcium signaling pathways, affecting various cellular activities such as secretion and cell signaling.
• Cell Proliferation and Differentiation: ANXA7 is involved in cell growth regulation and has been implicated in controlling the proliferation and differentiation of certain cell types.
• Tumor Suppression: ANXA7 has been identified as a tumor suppressor, with its loss or downregulation associated with the development and progression of certain cancers.

Interactions:

• Phospholipids: ANXA7 binds to phospholipid membranes in the presence of calcium, which is critical for its role in membrane dynamics.
• GTP-binding Proteins: ANXA7 interacts with GTP-binding proteins, which are involved in various signaling pathways and cellular processes.
• Protein Kinase C (PKC): ANXA7 is known to interact with PKC, influencing signal transduction pathways that regulate cellular responses.

Clinical Issues:

• Cancer: Alterations in ANXA7 expression have been linked to various cancers, including prostate, breast, and colorectal cancers. Its role as a tumor suppressor makes it a potential target for cancer therapy and a biomarker for cancer diagnosis.
• Neurological Disorders: Given its expression in the brain and involvement in calcium signaling, ANXA7 is implicated in neurological conditions, potentially affecting neural function and integrity.
• Cardiovascular Diseases: ANXA7's role in membrane dynamics and calcium signaling may impact cardiovascular health, contributing to conditions like heart disease and atherosclerosis.

Summary:

Annexin A7 (ANXA7) is a multifunctional protein that plays significant roles in membrane dynamics, calcium signaling, and cellular growth regulation. Its ability to bind phospholipid membranes and interact with various proteins highlights its importance in maintaining cellular homeostasis and responding to physiological changes. Clinically, ANXA7 is significant in cancer, neurological disorders, and cardiovascular diseases, making it a potential biomarker and therapeutic target. Understanding its diverse roles and interactions is essential for developing targeted therapies and diagnostic tools in these conditions.