Doublecortin

Function

Microtubule-associated protein required for initial steps of neuronal dispersion and cortex lamination during cerebral cortex development. May act by competing with the putative neuronal protein kinase DCLK1 in binding to a target protein. May in that way participate in a signaling pathway that is crucial for neuronal interaction before and during migration, possibly as part of a calcium ion-dependent signal transduction pathway. May be part with PAFAH1B1/LIS-1 of overlapping, but distinct, signaling pathways that promote neuronal migration.

Involvement in disease

Lissencephaly, X-linked 1

LISX1

A classic lissencephaly characterized by mental retardation and seizures that are more severe in male patients. Affected boys show an abnormally thick cortex with absent or severely reduced gyri. Clinical manifestations include feeding problems, abnormal muscular tone, seizures and severe to profound psychomotor retardation. Female patients display a less severe phenotype referred to as 'doublecortex'.

None

The disease is caused by variants affecting the gene represented in this entry.

Subcortical band heterotopia X-linked

SBHX

SBHX is a mild brain malformation of the lissencephaly spectrum. It is characterized by bilateral and symmetric plates or bands of gray matter found in the central white matter between the cortex and cerebral ventricles, cerebral convolutions usually appearing normal.

None

The disease is caused by variants affecting the gene represented in this entry.

A chromosomal aberration involving DCX is found in lissencephaly. Translocation t(X;2)(q22.3;p25.1).

Post-translational modifications

Phosphorylation by MARK1, MARK2 and PKA regulates its ability to bind microtubules (By similarity). Phosphorylation at Ser-265 and Ser-297 seems to occur only in neonatal brain, the levels falling precipitously by postnatal day 21 (By similarity).

Ubiquitinated by MDM2, leading to its degradation by the proteasome. Ubiquitinated by MDM2 and subsequent degradation leads to reduce the dendritic spine density of olfactory bulb granule cells.

Tissue specificity

Highly expressed in neuronal cells of fetal brain (in the majority of cells of the cortical plate, intermediate zone and ventricular zone), but not expressed in other fetal tissues. In the adult, highly expressed in the brain frontal lobe, but very low expression in other regions of brain, and not detected in heart, placenta, lung, liver, skeletal muscles, kidney and pancreas.

Cellular localization

• Cytoplasm
• Cell projection
• Neuron projection
• Localizes at neurite tips.

Alternative names

• Neuronal migration protein doublecortin
• Doublin
• Lissencephalin-X
• Lis-X
• LISX
• DBCN
• DCX

Database links

• entrezGene:1641
• omim:300121
• swissprot:O43602

Target type

Proteins

Primary research area

Neuroscience

Molecular weight

40574Da