చేదు: కూర్పుల మధ్య తేడాలు

{{అనువాదం}}

 

 

చేదు అనునది అన్ని రుచులలో అతి సున్నితమైన రుచి.

 

Research has shown that TAS2Rs (taste receptors, type 2, also known as T2Rs) such as [[TAS2R38]] coupled to the [[G protein]] [[gustducin]] are responsible for the human ability to taste bitter substances.<ref>{{cite journal |author=Maehashi, K., M. Matano, H. Wang, L. A. Vo, Y. Yamamoto, and L. Huang |title=Bitter peptides activate hTAS2Rs, the human bitter receptors |journal=Biochem Biophys Res Commun |volume=365 |year=2008 |pages=851–855 |doi=10.1016/j.bbrc.2007.11.070 |pmid=18037373 |issue=4|pmc=2692459}}</ref> They are identified not only by their ability to taste for certain "bitter" ligands, but also by the morphology of the receptor itself (surface bound, monomeric).<ref>{{cite journal | last=Lindemann | first=Bernd | title=Receptors and transduction in taste| journal=Nature |date=13 September 2001 | volume=413 |pages= 219–225|url=http://www.nature.com/nature/journal/v413/n6852/pdf/413219a0.pdf|format=PDF|accessdate=2007-12-30 | doi=10.1038/35093032| pmid=11557991 | issue=6852}}</ref> The TAS2R family in humans is thought to comprise about 25 different taste receptors, some of which can recognize a wide variety of bitter-tasting compounds.<ref>{{cite journal|last=Meyerhof|year=2010|doi=10.1093/chemse/bjp092|url=http://chemse.oxfordjournals.org/content/35/2/157.long}}</ref> Over 550 bitter-tasting compounds have been identified, of which about 100 have been assigned to one or more specific receptors.<ref>{{cite journal|last=Wiener|year=2012|doi=10.1093/nar/gkr755|url=http://nar.oxfordjournals.org/content/40/D1/D413.long|pmid=21940398|pmc=3245057|volume=40|issue=Database issue|title=BitterDB: a database of bitter compounds|journal=Nucleic Acids Res.|pages=D413–9}}</ref> Recently it is speculated that the selective constraints on the TAS2R family have been weakened due to the relatively high rate of mutation and pseudogenization.<ref>{{cite journal |author=Wang, X., S. D. Thomas, and J. Zhang |title=Relaxation of selective constraint and loss of function in the evolution of human bitter taste receptor genes |journal=Hum Mol Genet |volume=13 |year=2004 |pages=2671–2678|doi=10.1093/hmg/ddh289 |pmid=15367488 |issue=21}}</ref> Researchers use two synthetic substances, [[phenylthiocarbamide]] (PTC) and [[propylthiouracil|6-n-propylthiouracil]] (PROP) to study the [[genetics]] of bitter perception. These two substances taste bitter to some people, but are virtually tasteless to others. Among the tasters, some are so-called "[[supertaster]]s" to whom PTC and PROP are extremely bitter. The variation in sensitivity is determined by two common alleles at the TAS2R38 locus.<ref>{{cite journal|author=Wooding, S., U. K. Kim, M. J. Bamshad, J. Larsen, L. B. Jorde, and D. Drayna |title=Natural selection and molecular evolution in PTC, a bitter-taste receptor gene |journal=Am J Hum Genet |volume=74 |year=2004 |pages=637–646 |doi=10.1086/383092|pmid=14997422 |issue=4 |pmc=1181941}}</ref> This genetic variation in the ability to taste a substance has been a source of great interest to those who study genetics.

 

==ఇవి కూడా చూడండి==

==సూచికలు==

{{Reflist}}