Članovi trefoilske porodice karakteriziraju postojanje najmanje jedne kopije motiva trefoila, domena od 40 aminokiselina koja sadrži tri konzervirana disulfida. Oni su stabilni sekretorni proteini eksprimirani u gastrointestinalnojsluzokoži. Njihove funkcije nisu definirane, ali mogu zaštititi sluznicu od insulta, stabilizovati sloj sluzi i uticati na zarastanje epitela. Kodirani protein inhibira lučenje želučane kiseline. Ovaj gen i dva druga srodna gena člana porodice trefoila nalaze se u klasteru na hromosomu 21.[7]
Vezivanje glikana
Svi ljudski faktori trefoila su lektini koji specifično djeluju sa disaharidom GlcNAc-α-1,4-Gal.[8] Ovaj disaharid je neobičan glikotop za koji se zna da postoji samo na velikim, jako glikozilovanim, mucinima u sluznicama. Unakrsnim povezivanjem mucina putem dvovalentnog vezivanja ovog glikotopa, trefoilski faktori su tada u stanju da reverzibilno moduliraju debljinu i viskoznostsluzi.[8]
^"Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^"Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^Tomasetto C, Rockel N, Mattei MG, Fujita R, Rio MC (Sep 1992). "The gene encoding the human spasmolytic protein (SML1/hSP) is in 21q 22.3, physically linked to the homologous breast cancer marker gene BCEI/pS2". Genomics. 13 (4): 1328–30. doi:10.1016/0888-7543(92)90059-2. PMID1505966.
May FE, Westley BR (1997). "Close physical linkage of the genes encoding the pNR-2/pS2 protein and human spasmolytic protein (hSP)". Hum. Genet. 99 (3): 303–7. doi:10.1007/s004390050362. PMID9050913. S2CID22603186.
Seib T, Blin N, Hilgert K, et al. (1997). "The three human trefoil genes TFF1, TFF2, and TFF3 are located within a region of 55 kb on chromosome 21q22.3". Genomics. 40 (1): 200–2. doi:10.1006/geno.1996.4511. PMID9070946.
Berry A, Scott HS, Kudoh J, et al. (2001). "Refined localization of autosomal recessive nonsyndromic deafness DFNB10 locus using 34 novel microsatellite markers, genomic structure, and exclusion of six known genes in the region". Genomics. 68 (1): 22–9. doi:10.1006/geno.2000.6253. PMID10950923.
Bulitta CJ, Fleming JV, Raychowdhury R, et al. (2002). "Autoinduction of the trefoil factor 2 (TFF2) promoter requires an upstream cis-acting element". Biochem. Biophys. Res. Commun. 293 (1): 366–74. doi:10.1016/S0006-291X(02)00199-7. PMID12054609.