Evaluation of hydrophobicity versus chaperonelike activity of bovine alphaA- and alphaB-crystallin.
Calf lens alphaA-crystallin isolated by reversed-phase HPLC demonstrates a slightly more hydrophobic profile than alphaB-crystallin. Fluorescent probes in addition to bis-ANS, like cis-parinaric acid (PA) and pyrene, show higher quantum yields or Ham ratios when bound to alphaA-crystallin than to alphaB-crystallin at room temperature. Bis-ANS binding to both alphaA- and alphaB-crystallin decreases with increase in temperature. At room temperature, the chaperone-like activity of alphaA-crystallin is lower than that of alphaB-crystallin whereas at higher temperatures, alphaA-crystallin shows significantly higher protection against aggregation of substrate proteins compared to alphaB-crystallin. Therefore, calf lens alphaA-crystallin is more hydrophobic than alphaB-crystallin and chaperone-like activity of alpha-crystallin subunits is not quantitatively related to their hydrophobicity.
Bhattacharyya
Jaya
J
Department of Ophthalmology, University of Missouri, Columbia 65212, USA.
Srinivas
V
V
Sharma
K Krishna
KK
D000817:Anilino Naphthalenesulfonates / Q000378:metabolism; D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D004229:Dithiothreitol / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000737:chemistry / Q000378:metabolism; D005456:Fluorescent Dyes / Q000737:chemistry / Q000378:metabolism; D057927:Hydrophobic and Hydrophilic Interactions; D007328:Insulin / Q000378:metabolism; D018832:Molecular Chaperones / Q000378:metabolism*; D011721:Pyrenes / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013696:Temperature; D038202:alpha-Crystallin A Chain / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D038203:alpha-Crystallin B Chain / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*
D000817:Anilino Naphthalenesulfonates; D005231:Fatty Acids, Unsaturated; D005456:Fluorescent Dyes; D007328:Insulin; D018832:Molecular Chaperones; D011721:Pyrenes; D038202:alpha-Crystallin A Chain; D038203:alpha-Crystallin B Chain; C035763:5,5'-bis(8-(phenylamino)-1-naphthalenesulfonate); C030984:pyrene; C013641:parinaric acid; D004229:Dithiothreitol