Premium
The resilience of cancer‐specific protein galectin‐3: Implications in biological functions
Author(s) -
Dam Tarun,
Kadav Priyanka,
Welch Christina,
Edwards Jared,
Bandyopadhyay Purnima
Publication year - 2019
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.2019.33.1_supplement.798.4
Subject(s) - chemistry , galectin , collagenase , biochemistry , receptor , microbiology and biotechnology , enzyme , biology
Structural degradation is detrimental for protein activity and functions. We recently found that the tumor‐associated protein galectin‐3 (Gal‐3) is apparently an exception to this rule. Gal‐3 plays important roles in cancer but its functions are not fully understood. We have found that the affinity purified Gal‐3, when stored with lactose at 4°C for more than six weeks, undergoes complete degradation even in the absence of collagenases. Full‐length Gal‐3 after full degradation produced a single protein band of 17 kDa. This molecular weight is similar to that of the CRD (carbohydrate recognition domain) portion of Gal‐3. Conventionally, the CRD is separated from intact Gal‐3 by enzymatic digestion using collagenases. However, in the present case, Gal‐3 apparently self‐degraded to produce the CRD without the catalytic action of collagenases. Our data indicate that degradation of Gal‐3 significantly alters the protein but the CRD remains intact and functionally active. Like the full‐length Gal‐3, the CRDs interacted with thyroglobulin, chondroitin sulfate A and C. However, the CRDs could not cross‐link these multivalent ligands as revealed by our spectroscopic analysis. Our current observations suggest that Gal‐3 retains it ligand recognition properties even when it is substantially degraded in a challenging cellular environment. Thus the degraded Gal‐3 can still carry out some of the functions of intact Gal‐3. Although the CRDs retain the binding property of its intact precursor (Gal‐3), they lose the ability to cross‐link cellular receptors. As a result, the CRDs generated through degradation may influence cell signaling by competing with intact Gal‐3 for the same receptors in cellular environment. Support or Funding Information National Science Foundation This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .