The type I receptor serine/threonine kinases are also known as activin receptors or activin receptor-like kinases, ALKs, for which a systematic nomenclature has been proposed (ALK1-7). These receptors are responsible for signalling in response to transforming growth factor beta (TGFβ) [4]. These act as a heterodimer, where Type I RSTKs are phosphorylated by Type II RSTKs.

* Key recommended reading is highlighted with an asterisk

* Batlle E, Massagué J. (2019) Transforming Growth Factor-β Signaling in Immunity and Cancer. Immunity, 50 (4): 924-940. DOI: 10.1016/j.immuni.2019.03.024 [PMID:30995507]

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3. Li HY, Wang Y, Heap CR, King CH, Mundla SR, Voss M, Clawson DK, Yan L, Campbell RM, Anderson BD et al.. (2006) Dihydropyrrolopyrazole transforming growth factor-beta type I receptor kinase domain inhibitors: a novel benzimidazole series with selectivity versus transforming growth factor-beta type II receptor kinase and mixed lineage kinase-7. J Med Chem, 49 (6): 2138-42. [PMID:16539403]

4. Loomans HA, Andl CD. (2016) Activin receptor-like kinases: a diverse family playing an important role in cancer. Am J Cancer Res, 6 (11): 2431-2447. [PMID:27904762]

5. Melisi D, Ishiyama S, Sclabas GM, Fleming JB, Xia Q, Tortora G, Abbruzzese JL, Chiao PJ. (2008) LY2109761, a novel transforming growth factor beta receptor type I and type II dual inhibitor, as a therapeutic approach to suppressing pancreatic cancer metastasis. Mol Cancer Ther, 7 (4): 829-40. [PMID:18413796]