Fibronectin type III domain explained

The Fibronectin type III domain is an evolutionarily conserved protein domain that is widely found in animal proteins. The fibronectin protein in which this domain was first identified contains 16 copies of this domain. The domain is about 100 amino acids long and possesses a beta sandwich structure. Of the three fibronectin-type domains, type III is the only one without disulfide bonding present. Fibronectin domains are found in a wide variety of extracellular proteins. They are widely distributed in animal species, but also found sporadically in yeast, plant and bacterial proteins.

Human proteins containing this domain

ABI3BP

ANKFN1; ASTN2; AXL; BOC; BZRAP1; C20orf75; CDON;CHL1

CMYA5; CNTFR; CNTN1; CNTN2; CNTN3; CNTN4; CNTN5;CNTN6

COL12A1; COL14A1; COL20A1; COL7A1; CRLF1; CRLF3; CSF2RB;CSF3R

DCC; DSCAM; DSCAML1; EBI3; EGFLAM; EPHA1; EPHA10;EPHA2

EPHA3; EPHA4; EPHA5; EPHA6; EPHA7; EPHA8; EPHB1;EPHB2

EPHB3; EPHB4; EPHB6; EPOR; FANK1; FLRT1; FLRT2;FLRT3

FN1; FNDC1; FNDC3A; FNDC3B; FNDC4; FNDC5; FNDC7;FNDC8

FSD1; FSD1L; FSD2; GHR; HCFC1; HCFC2; HUGO;IFNGR2

IGF1R; IGSF22; IGSF9; IGSF9B; IL4R; IL11RA; IL12B; IL12RB1;IL12RB2

IL20RB; IL23R; IL27RA; IL31RA; IL6R; IL6ST; IL7R;INSR

INSRR; ITGB4; KAL1; KALRN; L1CAM; LEPR;LIFR

LRFN2; LRFN3; LRFN4; LRFN5; LRIT1; LRRN1; LRRN3;MERTK

MID1; MID2; MPL; MYBPC1; MYBPC2; MYBPC3; MYBPH;MYBPHL

MYLK; MYOM1; MYOM2; MYOM3; NCAM1; NCAM2; NEO1;NFASC

NOPE; NPHS1; NRCAM; OBSCN; OBSL1; OSMR; PHYHIP;PHYHIPL

PRLR; PRODH2; PTPRB; PTPRC; PTPRD; PTPRF; PTPRG;PTPRH

PTPRJ; PTPRK; PTPRM; PTPRO; PTPRS; PTPRT; PTPRU;PTPRZ1

PTPsigma; PUNC; RIMBP2; ROBO1; ROBO2; ROBO3; ROBO4;ROS1

SDK1; SDK2; SNED1; SORL1; SPEG; TEK; TIE1;TNC

TNN; TNR; TNXB; TRIM36; TRIM42; TRIM46; TRIM67;TRIM9

TTN; TYRO3; UMODL1; USH2A; VASN; VWA1; dJ34F7.1;fmi

See also

• Monobodies are engineered (synthetic) antibody mimetics based on a fibronectin type III domain (specifically, the 10th FN3 domain of human fibronectin). Monobodies feature either diversified loops or diversified strands of a flat beta-sheet surface, which serve as interaction epitopes. Monobody binders have been selected a wide variety of target molecules, and have expanded beyond the potential range of binding interfaces observed in both natural and synthetic antibodies.

References

• Bazan JF . Structural design and molecular evolution of a cytokine receptor superfamily . Proceedings of the National Academy of Sciences of the United States of America . 87 . 18 . 6934–8 . September 1990 . 2169613 . 54656 . 10.1073/pnas.87.18.6934 . 1990PNAS...87.6934B . free .
• Little E, Bork P, Doolittle RF . Tracing the spread of fibronectin type III domains in bacterial glycohydrolases . Journal of Molecular Evolution . 39 . 6 . 631–43 . December 1994 . 7528812 . 10.1007/bf00160409 . 1994JMolE..39..631L . 11909704 .
• Kornblihtt AR, Umezawa K, Vibe-Pedersen K, Baralle FE . Primary structure of human fibronectin: differential splicing may generate at least 10 polypeptides from a single gene . The EMBO Journal . 4 . 7 . 1755–9 . July 1985 . 10.1002/j.1460-2075.1985.tb03847.x . 2992939 . 554414 .