南極海の胚で,低代謝コストで高マクロ分子合成が行われる

A G Marsh¹, R E Maxson, D T Manahan

¹Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA.

Science (New York, N.Y.)

|March 10, 2001

まとめ

南極海の胚は,その発達において驚くべき温度補償を示している. 低温にもかかわらず,彼らのRNAとタンパク質合成率は温帯の種に匹敵し,生物圏の限界での生存を可能にします.

科学分野:

マリン・バイオロジーマリン・バイオロジー
発達生物学発達生物学について
バイオケミストリーバイオケミストリー

背景:

生物が極端な環境でどのように生き延びるかを理解することは,生物圏の限界を定義する上で極めて重要です.
低温は通常,代謝活動と合成速度の低下と相関する.

研究の目的:

-1.5°Cでの南極海の胚の早期発達のエネルギーコストを評価する.
極端な寒さに反応するマクロ分子 (RNAとタンパク質) の転機率を調査する.

主な方法:

開発初期における南極海の胚におけるRNAとタンパク質合成率の測定.
これらの割合を温帯海の胚と比較.

主要な成果:

南極の胚のタンパク質とRNAの合成率は,温帯の胚のタンパク質とRNAの合成率に相当し,温度補償を示した.
低温でのこの高い合成速度は,タンパク質のターンオーバー (0.45 J/mgタンパク質) のエネルギーコストが著しく低いため,エネルギー的に実現可能である.

結論:

南極海の胚は,発達のための高い代謝能力を示しており,低温の影響に関する仮定に挑戦しています.
タンパク質のターンボールの低エネルギーコストは,極端に寒い環境で高い代謝率を可能にするために重要です.
この適応により,海は生物圏の縁で繁栄することができます.

さらに関連する動画

09:03

Semiconductor Sequencing for Preimplantation Genetic Testing for Aneuploidy

Published on: August 25, 2019

05:13

Establishment of an Embryo Implantation Model In Vitro

Published on: June 21, 2024

関連する概念動画

01:38

Fertilization

During fertilization, an egg and sperm cell fuse to create a new diploid structure. In humans, the process occurs once the egg has been released from the ovary, and travels into the fallopian tubes. The process requires several key steps: 1) sperm present in the genital tract must locate the egg; 2) once there, sperm need to release enzymes to help them burrow through the protective zona pellucida of the egg; and 3) the membranes of a single sperm cell and egg must fuse, with the sperm...

01:33

Cleavage and Blastulation

After a large-single-celled zygote is produced via fertilization, the process of cleavage occurs while zygotes travel through the uterine tube. Cleavage is a mitotic cell division that does not result in growth. With each round of successive cell division, daughter cells get increasingly smaller.

02:59

Animal Mitochondrial Genetics

Among all the organelles in an animal cell, only mitochondria have their own independent genomes. Animal mitochondrial DNA is a double-stranded, closed-circular molecule with around 20,000 base pairs. Mitochondrial DNA is unique in that one of its two strands, the heavy, or H, -strand is guanine rich, whereas the complementary strand is cytosine rich and called the light, or L, -strand. Compared to nuclear DNA, mitochondrial DNA has a very low percentage of non-coding regions and is marked by...

01:28

ATP and Macromolecule Synthesis

Biological macromolecules are organic compounds, predominantly composed of carbon atoms. The carbon atoms are covalently bonded with hydrogen, oxygen, nitrogen, and other minor elements. There are four major biological macromolecule classes: carbohydrates, lipids, proteins, and nucleic acids.
Most macromolecules are composed of single subunits, or building blocks, called monomers. The monomers combine with each other using covalent bonds to form larger molecules known as polymers.
Conversion of...

01:29

Biosynthesis of Lipids

Microbial membranes exhibit remarkable diversity in lipid composition, reflecting evolutionary adaptations to various environmental conditions. The three domains of life—Bacteria, Archaea, and Eukarya—synthesize membrane lipids through distinct biosynthetic pathways, leading to fundamental structural differences that impact membrane stability, function, and adaptability.Fatty Acid-Based Lipids in Bacteria and EukaryaBacteria and eukaryotes share a common fatty acid biosynthesis pathway, which...

01:30

Production of Pharmaceuticals

Industrial insulin production uses genetically engineered E. coli expressing a proinsulin gene controlled by a tryptophan promoter and containing a methionine linker for later cleavage. The cells also carry ampicillin resistance for selective growth. Seed cultures are stored at −80 °C and production begins by thawing a small amount to inoculate starter cultures, which are progressively scaled to a 50,000-L bioreactor. In the bioreactor, E. coli grow in nutrient-rich media under sterile, tightly...

関連する実験動画