Overview
- Peptide (C)EVSKPLAHHIPVEK, corresponding to amino acid residues 91-104 of human MANF (Accession P55145). Mature MANF protein.
- Rat and mouse brain sections (1:80).
- Expression of MANF in rat and mouse hippocampusImmunohistochemical staining of rat and mouse brain sections using Anti-MANF/ARMET-ATTO Fluor-594 Antibody (#ANT-028-AR), (1:80). A. MANF staining (red) in rat is detected in hippocampal dentate gyrus region in the cell soma (vertical arrows) and few astrocytes (horizontal arrow). B. MANF staining (red) is detected in same regions from mouse brain sections. Nuclei are stained using DAPI as the counterstain (blue).
The novel protein mesencephalic astrocyte-derived neurotrophic factor (MANF) is a survival molecule (alternatively referred to as arginine-rich, mutated in early stage tumors, or ARMET) that has high selectivity for dopaminergic neurons of the midbrain1,2. There, it induces proliferative and protective effects against neurodegeneration (usually caused by 6-hydroxydopamine); its therapeutic potential in dopamine-related neurodegenerative disorders such as Parkinson's disease is therefore promising3,4. MANF is also expressed cardiac tissues. As was recently suggested, it induces cardioprotection in the heart and anti-hypertrophic effects via reducing endoplasmic reticulum stress in ischemic conditions in both the heart and the brain – thus, its effects stretch beyond rescue and protection of dopaminergic neurons alone1,5.
Generally, neurotrophic factors (NTFs) provide support, protection, and regulation for neurons – with each group of neurons having their own unique NTFs – both during development and at adulthood. Other noticeable NTFs include neurotrophin-3 and -4 (NT3 and NT4), nerve growth factor (NGF), brain derived neurotrophic factor (BDNF), and glial cell derived neurotrophic factor (GDNF)6.
MANF is considered to be evolutionary conserved within Mammalia and beyond (including distant species such as nematode and fruit fly – the latter shares more than 50% identity with human MANF gene) and is highly mutative in many tumors. It is mostly composed of alpha helices and random coils; its structure essentially differs from any other neurotrophic factor. It is suggested that the protein initiates intracellular signaling cascade by binding to cell-surface lipids and membranes via its cysteine-rich N-terminal. Together with its C-terminal which contains a disulfide bridge that endows a cytoprotective response against ER stress, MANF is implied to be bi-functional3,7.