We employed the first principles computational method MembStruk and homology modeling techniques to predict the 3D structures of the human phenylthiocarbamide (PTC) taste receptor. This protein is a seven-transmembrane-domain G protein-coupled receptor that exists in two main forms worldwide, designated taster and nontaster, which differ from each other at three amino-acid positions. 3D models ...

A sibship with four cases of hereditary elliptocytic anaemia is described. The condition in this family may have arisen as a mutation in the mother of the sibship; affected members were unable to taste phenylthiocarbamide while normal members were tasters. Experiments with (32)P-orthophosphate in vitro did not show any evidence of biochemical upset as found in hereditary spherocytosis; thus a c...

OBJECTIVE The aim of this study was to investigate the relationship of taster status with taste detection and recognition thresholds for sucrose and quinine. DESIGN Sixty-nine subjects (35 men and 34 women; mean age, 23.9+/-1.2 years) were included. Stimulus fluids were prepared, one each for phenylthiocarbamide (PTC), 6-n-propylthiouracil (PROP), sucrose and quinine HCl. In each series, succ...

Zebrafish have long been utilized to study the cellular and molecular mechanisms of development by time-lapse imaging of the living transparent embryo. Here we describe a method to mount zebrafish embryos for long-term imaging and demonstrate how to automate the capture of time-lapse images using a confocal microscope. We also describe a method to create controlled, precise damage to individual...

The ability or inability to taste the compound phenylthiocarbamide (PTC) is a classic inherited trait in humans and has been the subject of genetic and anthropological studies for over 70 years. This trait has also been shown to correlate with a number of dietary preferences and thus may have important implications for human health. The recent identification of the gene that underlies this phen...

Although human bitter taste perception is hypothesized to be a dietary adaptation, little is known about genetic signatures of selection and patterns of bitter taste perception variability in ethnically diverse populations with different diets, particularly from Africa. To better understand the genetic basis and evolutionary history of bitter taste sensitivity, we sequenced a 2,975 bp region en...

The evidence implicating iodine deficiency in the aetiology of endemic goitre is overwhelming, and a deficiency of iodine in the diet has been accepted as the main cause of this condition (Kelly and Snedden, I960; Greer, I962; Wayne, Koutras, and Alexander, I964). Considerations of the quantitative aspects of iodine metabolism leave little doubt that in the presence of a sufficiently severe and...

Thiacalix[4]arene receptors with two thiourea moieties and 2-pyridyl exhibited a heteroditopic dinuclear receptor F ? Ag + ions by positive allosteric effect.

T2Rs (bitter taste-sensing type 2 receptors) are expressed in the oral cavity to prevent ingestion of dietary toxins through taste avoidance. They are also expressed in other cell types, including gut enteroendocrine cells, where their physiological role is enigmatic. Previously, we proposed that T2R-dependent CCK (cholecystokinin) secretion from enteroendocrine cells limits absorption of dieta...

The ability to taste the bitter compound phenylthiocarbamide (PTC) and related chemicals is bimodal, and all human populations tested to date contain some people who can and some people who cannot taste PTC. Why this trait has been maintained in the population is uncertain but this polymorphism may influence food selection, nutritional status or thyroid metabolism. The gene product that gives r...