遺伝子スイッチングと臭味受容体の遺伝子選択の安定性

Benjamin M Shykind¹, S Christy Rohani, Sean O'Donnell

¹Department of Biochemistry and Molecular Biophysics and Howard Hughes Medical Institute, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA.

Cell

|June 10, 2004

まとめ

嗅覚センサーニューロンは通常,1つの嗅覚受容体を発現します. この研究では,未成熟の神経細胞は受容体を切り替えることができるが,機能的受容体発現は,細胞の生涯にわたってこの選択を安定させる.

科学分野:

神経科学は神経科学である.
遺伝学遺伝学とは
嗅覚受容体の研究

背景:

嗅覚センサーニューロン (OSN) は,単一のオロラント受容体 (OR) 遺伝子を発現し,これは嗅覚知覚モデルにとって重要な原則です.
OSNにおける安定した,単一のOR表現を保証するメカニズムは,まだ完全に理解されていません.

研究の目的:

嗅覚感覚ニューロンにおける嗅覚受容体遺伝子選択の安定性を調査する.
嗅覚感覚ニューロンが発達中に受容体発現を切り替えるかどうか,そしてどのように切り替えるかを決定する.

主な方法:

OSNにおける受容体遺伝子発現を追跡および分析するための遺伝的戦略の開発.
変異した受容体遺伝子を持つものを含む未成熟および成熟の嗅覚感覚ニューロンにおける受容体発現の観察.

主要な成果:

未成熟の嗅覚感覚ニューロンは,発現した嗅覚受容体を切り替えることができるが,これはまれである.
機能的な嗅覚受容体を発現するニューロンは,受容体のスイッチングが著しく減少しています.
ミュータント受容体遺伝子発現は受容体遺伝子のスイッチングの可能性を高めます.

結論:

機能的嗅覚受容体の発現は,受容体遺伝子の切り替えを終了するフィードバック信号を提供します.
このフィードバックメカニズムは,それぞれのニューロンが最終的に,その寿命を通して安定した,機能的なオドラント受容体を表現することを保証します.
発見は,単一の安定した嗅覚受容体発現を確保する過程を明確にします.

さらに関連する動画

12:02

High-throughput Analysis of Mammalian Olfactory Receptors: Measurement of Receptor Activation via Luciferase Activity

Published on: June 2, 2014

11.6K

09:53

Real-time In Vitro Monitoring of Odorant Receptor Activation by an Odorant in the Vapor Phase

Published on: April 23, 2019

6.5K

関連する概念動画

01:25

Olfaction

40.5K

The sense of smell is achieved through the activities of the olfactory system. It starts when an airborne odorant enters the nasal cavity and reaches olfactory epithelium (OE). The OE is protected by a thin layer of mucus, which also serves the purpose of dissolving more complex compounds into simpler chemical odorants. The size of the OE and the density of sensory neurons varies among species; in humans, the OE is only about 9-10 cm2.
The olfactory receptors are embedded in the cilia of the...

40.5K

02:32

Position-effect Variegation

5.6K

In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread out in the interphase nucleus, others do not. He termed them euchromatin and heterochromatin, respectively. He proposed that the heterochromatin regions reflect a functionally inactive state of the genome. It was later confirmed that heterochromatin is transcriptionally repressed, and euchromatin is transcriptionally active chromatin.

5.6K

02:08

Gene Conversion

9.2K

Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...

9.2K

02:27

Background and Environment Affect Phenotype

5.9K

Although the genetic makeup of an organism plays a major role in determining the phenotype, there are also several environmental factors, such as temperature, oxygen availability, presence of mutagens, that can alter an organism’s phenotype.
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...

5.9K

01:21

G-Protein Gated Ion Channels

5.5K

GPCRs are primarily responsible for our sense of smell, taste, and vision. The binding of a sensory stimulus activates GPCR to stimulate effector proteins, many of which are ion channels in the sensory organs. GPCRs modulate the opening and closing of the target ion channels either directly by binding them, or by releasing second messengers that activate these channels. As ions move across the membrane, the membrane potential is altered, which induces an appropriate response.
Sensory...

5.5K

01:03

Olfactory Receptors: Location and Structure

10.6K

The process of olfaction, also known as the sense of smell, is a sophisticated chemical response system. The specialized sensory neurons that facilitate this process, known as olfactory receptor neurons, are situated in an upper segment of the nasal cavity, known as the olfactory epithelium. Olfactory sensory neurons are bipolar, with their dendrites extending from the epithelium's apex into the mucus that lines the nasal cavity. Airborne molecules, when inhaled, traverse the olfactory...