Interactions between the breast cancerassociated MUC1 mucins and C-type lectin characterized by optical tweezers

TY - JOUR

T1 - Interactions between the breast cancerassociated MUC1 mucins and C-type lectin characterized by optical tweezers

AU - Hadjialirezaei, Soosan

AU - Picco, Gianfranco

AU - Beatson, Richard

AU - Burchell, Joy

AU - Stokke, Bjørn Torger

AU - Sletmoen, Marit

PY - 2017/4/1

Y1 - 2017/4/1

N2 - Carbohydrate-protein interactions govern many crucial processes in biological systems including cell recognition events. We have used the sensitive force probe optical tweezers to quantify the interactions occurring between MGL lectins and MUC1 carrying the cancerassociated glycan antigens mucins Tn and STn. Unbinding forces of 7.6 pN and 7.1 pN were determined for the MUC1(Tn)-MGL and MUC1(STn)-MGL interactions, at a force loading rate of ∼40 pN/s. The interaction strength increased with increasing force loading rate, to 27 and 37 pN at a force loading rate of ∼ 310 pN/s. No interactions were detected between MGL and MUC1(ST), a glycoform of MUC1 also expressed by breast carcinoma cells. Interestingly, this glycan (ST) can be found on proteins expressed by normal cells, although in this case not on MUC1. Additionally, GalNAc decorated polyethylene glycol displayed similar rupture forces as observed for MUC1(Tn) and MUC1(STn) when forced to unbind from MGL, indicating that GalNAc is an essential group in these interactions. Since the STn glycan decoration is more frequently found on the surface of carcinomas than the Tn glycan, the binding of MUC1 carrying STn to MGL may be more physiologically relevant and may be in part responsible for some of the characteristics of STn expressing tumours.

AB - Carbohydrate-protein interactions govern many crucial processes in biological systems including cell recognition events. We have used the sensitive force probe optical tweezers to quantify the interactions occurring between MGL lectins and MUC1 carrying the cancerassociated glycan antigens mucins Tn and STn. Unbinding forces of 7.6 pN and 7.1 pN were determined for the MUC1(Tn)-MGL and MUC1(STn)-MGL interactions, at a force loading rate of ∼40 pN/s. The interaction strength increased with increasing force loading rate, to 27 and 37 pN at a force loading rate of ∼ 310 pN/s. No interactions were detected between MGL and MUC1(ST), a glycoform of MUC1 also expressed by breast carcinoma cells. Interestingly, this glycan (ST) can be found on proteins expressed by normal cells, although in this case not on MUC1. Additionally, GalNAc decorated polyethylene glycol displayed similar rupture forces as observed for MUC1(Tn) and MUC1(STn) when forced to unbind from MGL, indicating that GalNAc is an essential group in these interactions. Since the STn glycan decoration is more frequently found on the surface of carcinomas than the Tn glycan, the binding of MUC1 carrying STn to MGL may be more physiologically relevant and may be in part responsible for some of the characteristics of STn expressing tumours.

UR - http://www.scopus.com/inward/record.url?scp=85017574733&partnerID=8YFLogxK

U2 - 10.1371/journal.pone.0175323

DO - 10.1371/journal.pone.0175323

M3 - Article

AN - SCOPUS:85017574733

SN - 1932-6203

VL - 12

JO - PL o S One

JF - PL o S One

IS - 4

M1 - e0175323

ER -