CRKL (CRK-like proto-oncogene) is a gene encoding an adaptor protein that plays critical roles in intracellular signal transduction. The protein contains SH2 and SH3 domains that mediate protein-protein interactions, linking various upstream receptors to downstream signaling pathways including RAS, JNK, and ERK. CRKL is essential for normal development and has been extensively studied for its role in cancer and leukemia. [1]
| Attribute | Value | [2]
|-----------|-------| [3]
| Gene Symbol | CRKL | [4]
| Gene Name | CRK-like proto-oncogene adaptor protein | [5]
| Chromosomal Location | 22q11.21 | [6]
| Entrez Gene ID | 1399 | [7]
| UniProt ID | P46109 | [8]
| Protein Length | 303 amino acids | [9]
| Molecular Weight | ~34 kDa | [10]
The CRKL gene is located on chromosome 22q11.21, within a region commonly deleted in DiGeorge syndrome (22q11.2 deletion syndrome). The gene spans approximately 12 kb and consists of 12 exons that encode the 303-amino acid adaptor protein.
CRKL is expressed ubiquitously in human tissues, with highest expression in:
CRKL expression is regulated by multiple mechanisms:
CRKL contains three conserved protein domains:
| Domain | Position | Function |
|---|---|---|
| SH2 domain | 6-106 aa | Binds phosphotyrosine-containing motifs |
| N-terminal SH3 | 126-180 aa | Proline-rich motif binding |
| C-terminal SH3 | 237-293 aa | Protein interaction hub |
| Property | Description |
|---|---|
| Binding partners | Over 50 known interactors |
| Post-translational modification | Tyrosine phosphorylation, SUMOylation |
| Subcellular localization | Cytoplasm, plasma membrane |
| Half-life | ~8 hours in cultured cells |
CRKL is a key intermediate in receptor tyrosine kinase (RTK) signaling to the RAS pathway:
RTK activation → GRB2/SOS recruitment → RAS activation → RAF → MEK → ERK
↑
CRKL (adaptor)
CRKL bridges receptor activation to RAS guanine nucleotide exchange, amplifying MAPK signaling.
CRKL contributes to JNK pathway activation through multiple mechanisms:
In chronic myeloid leukemia (CML), CRKL is a critical substrate of BCR-ABL:
| Cancer Type | CRKL Role | Clinical Relevance |
|---|---|---|
| Chronic myeloid leukemia | BCR-ABL substrate | Marker of BCR-ABL activity |
| Gastric cancer | Oncogenic driver | Prognostic marker |
| Pancreatic cancer | Metastasis promoter | Therapeutic target |
| Breast cancer | Growth promoter | Biomarker potential |
| Melanoma | Invasion mediator | Resistance mechanism |
| Liver cancer | Tumor progression | Poor prognosis |
Recent research has identified connections between CRKL and Parkinson's disease:
| Mechanism | Evidence |
|---|---|
| Growth factor signaling | CRKL mediates neurotrophin signaling |
| Cellular stress response | CRKL activates stress-responsive kinases |
| Synaptic plasticity | CRKL in postsynaptic density signaling |
| Partner | Interaction Type | Function |
|---|---|---|
| BCR-ABL | Phosphorylation substrate | Leukemogenic signaling |
| GRB2 | SH3 binding | RTK signaling adaptor |
| SOS1 | SH3 binding | RAS activation |
| C3G | SH3 binding | RAP1 activation |
| ABL1 | SH3 binding | Tyrosine kinase substrate |
| CRK | Homology | Functional homolog |
| GAB1 | SH2 binding | PI3K-AKT pathway |
| EGFR | Phosphorylation | RTK signaling |
| PDGFRA | Phosphorylation | Growth factor signaling |
| LRRK2 | Potential interaction | PD-associated kinase |
CRKL participates in multiple signaling pathways:
Crkl knockout mice exhibit:
Gu et al. CRKL in integrin signaling (2002). 2002. ↩︎
Lafayette et al. CRKL in neuronal signaling (2019). 2019. ↩︎
Pendergast et al. BCR-ABL signal transduction (2002). 2002. ↩︎
Cheng et al. CRKL in melanoma (2017). 2017. ↩︎
Huang et al. CRKL polymorphisms and cancer (2015). 2015. ↩︎
Mandal et al. CRKL in chemoresistance (2021). 2021. ↩︎
Satoh et al. CRKL in liver cancer (2016). 2016. ↩︎
Knoblock et al. CRKL and 22q11.2 syndrome (2009). 2009. ↩︎
Uozumi et al. CRKL phosphorylation by SRC (2000). 2000. ↩︎
Gourbatsis et al. CRKL in hematopoiesis (2009). 2009. ↩︎