GDNF Antibody: ATTO 488

Glial cell line-derived neurotrophic factor (GDNF), a highly conserved multifunctional secretory protein, is distributed throughout the peripheral and central nervous system to support neuronal growth, proliferation, and survival (1-3). It was the first member of the GDNF family ligands (GFL). Pro-GDNF, a 211 residue precursor sequence, folds via disulphide bonding and dimerization in the endoplasmic reticulum (ER). N-linked glycosylation subsequently takes place at the tip of one of the protein’s two finger-like structures. These structures facilitate contact between the mature protein, the GRFα1 receptor, and RET, that is necessary for GDNF signalling. A similar configuration is observed in the cytokine TGFβ2 (2). The mature GDNF protein (134 residues) is produced by proteolysis of processed pro-GDNF at a proteolytic consensus sequence situated within the C-terminus (1). Through interactions between Cys131, Cys133, Cys68 & Cys72, the C-terminus forms a ring-like structure (3). As multiple proteases can cleave the precursor sequence, different forms of mature GDNF are possible (1). GDNF is implicated in the promotion of dopamine uptake within midbrain dopaminergic neurons, as well as the proliferation and migration of gliomas. Motor neurons, Schwann cells, oligodendrocytes, astrocytes, and skeletal muscle have been shown to secrete GDNF during neuronal development and growth (1,3). Initial studies suggested that GDNF may play a neuroprotective role in neurodegenerative disease such as amyotrophic lateral sclerosis (ALS), Parkinson’s disease and various synucleinopathies (4,5), however, recent research has indicated inconsistent levels of neuroprotective ability in neurodegenerative disease models (1, 6-8).

In the brain, predominantly expressed in the striatum with highest levels in the caudate and lowest in the putamen. Isoform 2 is absent from most tissues except for low levels in intestine and kidney. Highest expression of isoform 3 is found in pancreatic islets. Isoform 5 is expressed at very low levels in putamen, nucleus accumbens, prefrontal cortex, amygdala, hypothalamus and intestine. Isoform 3 is up-regulated in the middle temporal gyrus of Alzheimer disease patients while isoform 2 shows no change.

1. Cintrón-Colón A.F., et al. 2020. Cell Tissue Res. 382(1): 47-56. 2. Airaksninen M.S. et al. 2006. Brain Behav Evol. 68(3): 181-90. 3. Oh-hashi K. et al. 2009. Mol Cell Biochem. 323(1-2): 1-7. 4. Kearns C.M. & Gash D.M. 1995. Brain Res. 672(1-2): 101-111. 5. Nutt J.G. et al. 2003. Neurology. 60(1): 69-73. 6. Decressac M. et al. 2011. Brain. 13(8): 2302-2311. 7. Barker R.A. et al. 2020. J Parkinsons Dis. 10(3): 875-891. 8. Penttinen A.M. et al. 2018. Front Neurol. 9: 457.