2Z73 MEMBRANE PROTEIN, VISUAL PIGMENT, GQ-TYPE, G-PROTEIN COUPLED RECEPTOR, CHROMOPHORE, GLYCOPROTEIN, LIPOPROTEIN, MEMBRANE, PALMITATE, PHOSPHORYLATION, PHOTORECEPTOR PROTEIN, RETINAL PROTEIN, SENSORY TRANSDUCTION, TRANSDUCER, TRANSMEMBRANE, VISION CRYSTAL STRUCTURE OF SQUID RHODOPSIN