GLI3

Function

Has a dual function as a transcriptional activator and a repressor of the sonic hedgehog (Shh) pathway, and plays a role in limb development. The full-length GLI3 form (GLI3FL) after phosphorylation and nuclear translocation, acts as an activator (GLI3A) while GLI3R, its C-terminally truncated form, acts as a repressor. A proper balance between the GLI3 activator and the repressor GLI3R, rather than the repressor gradient itself or the activator/repressor ratio gradient, specifies limb digit number and identity. In concert with TRPS1, plays a role in regulating the size of the zone of distal chondrocytes, in restricting the zone of PTHLH expression in distal cells and in activating chondrocyte proliferation. Binds to the minimal GLI-consensus sequence 5'-GGGTGGTC-3'.

Involvement in disease

Greig cephalo-poly-syndactyly syndrome

GCPS

Autosomal dominant disorder affecting limb and craniofacial development. It is characterized by pre- and postaxial polydactyly, syndactyly of fingers and toes, macrocephaly and hypertelorism.

None

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

Pallister-Hall syndrome

PHS

An autosomal dominant disorder characterized by a wide range of clinical manifestations. Clinical features include hypothalamic hamartoma, pituitary dysfunction, central or postaxial polydactyly, and syndactyly. Malformations are frequent in the viscera, e.g. anal atresia, bifid uvula, congenital heart malformations, pulmonary or renal dysplasia.

None

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

Polydactyly, postaxial A1

PAPA1

A condition characterized by the occurrence of supernumerary digits in the upper and/or lower extremities. In postaxial polydactyly type A, the extra digit is well-formed and articulates with the fifth or a sixth metacarpal/metatarsal.

None

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

Polydactyly, postaxial B

PAPB

A condition characterized by an extra digit in the occurrence of supernumerary digits in the upper and/or lower extremities. In postaxial polydactyly type B the extra digit is not well formed and is frequently in the form of a skin.

None

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

Polydactyly, preaxial 4

PPD4

A form of polydactyly, a condition defined by the occurrence of supernumerary digits in the upper and/or lower extremities. Preaxial or radial polydactyly refers to the presence of extra digits on the radial side of the hand. PPD4 is an autosomal dominant form characterized by mild duplication of the thumb, syndactyly of various degrees affects fingers 3 and 4, duplication of part or all of the first or second toes and variable toes syndactyly. Some patients have only foot involvement.

None

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

Post-translational modifications

Phosphorylated on multiple sites by protein kinase A (PKA) and phosphorylation by PKA primes further phosphorylation by CK1 and GSK3. Phosphorylated by DYRK2 (in vitro). Phosphorylation is essential for its proteolytic processing.

Transcriptional repressor GLI3R, a C-terminally truncated form, is generated from the full-length GLI3 protein (GLI3FL/GLI3-190) through proteolytic processing. This process requires PKA-primed phosphorylation of GLI3, ubiquitination of GLI3 and the presence of BTRC. GLI3FL is complexed with SUFU in the cytoplasm and is maintained in a neutral state. Without the Hh signal, the SUFU-GLI3 complex is recruited to cilia, leading to the efficient processing of GLI3FL into GLI3R. GLI3R formation leads to its dissociation from SUFU, allowing it to translocate into the nucleus, and repress Hh target genes. When Hh signaling is initiated, SUFU dissociates from GLI3FL and this has two consequences. First, GLI3R production is halted. Second, free GLI3FL translocates to the nucleus, where it is phosphorylated, destabilized, and converted to a transcriptional activator (GLI3A). Phosphorylated in vitro by ULK3.

Sequence similarities

Belongs to the GLI C2H2-type zinc-finger protein family.

Tissue specificity

Is expressed in a wide variety of normal adult tissues, including lung, colon, spleen, placenta, testis, and myometrium.

Cellular localization

• Nucleus
• Cytoplasm
• Cell projection
• Cilium
• GLI3FL is localized predominantly in the cytoplasm while GLI3R resides mainly in the nucleus. Ciliary accumulation requires the presence of KIF7 and SMO. Translocation to the nucleus is promoted by interaction with ZIC1.

Alternative names

• Transcriptional activator GLI3
• GLI3 form of 190 kDa
• GLI3 full-length protein
• GLI3-190
• GLI3FL
• GLI3

Database links

• entrezGene:2737
• omim:165240
• swissprot:P10071

Target type

Proteins

Primary research area

Oncology

Other research areas

• Neuroscience

Molecular weight

169863Da