トウモロコシのゲノム内の遺伝子間の領域にレトロトランポゾンが巣を作っている

P SanMiguel¹, A Tikhonov, Y K Jin

¹Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA.

Science (New York, N.Y.)

|November 1, 1996

まとめ

トウモロコシのゲノムは,主に繰り返しDNA,特にレトロトランスポゾンで構成されています. これらの移動性遺伝要素は,遺伝子領域内に散らばっており,ゲノム組織に影響を与えます.

科学分野:

ゲノミクスゲノミクスとは
分子生物学は分子生物学である.
植物科学植物科学について

背景:

ユカリオットゲノムにおける遺伝子の複雑な組織と重複するDNAは,依然として重要な研究分野である.
複雑なゲノムの構造を理解することは,遺伝子調節と進化過程の解読に不可欠です.

研究の目的:

Adh1-Fとu22遺伝子を中心に,トウモロコシゲノム内の特定の280キロベース領域の構成と組織の調査.
このゲノム領域内の繰り返しDNA要素,特にレトロトランスポゾンを特定し,特徴づけること.

主な方法:

280キロベースのトウモロコシのゲノム領域の診断シーケンシング.
レトロエレメントファミリーの識別と特徴とそのコピー番号.
総ゲノム組成に対するレトロトランポゾン貢献の定量化.

主要な成果:

分析されたトウモロコシのゲノム領域は,主にレトロトランポゾンで構成されており,10の異なるレトロエレメントファミリーが特定されています.
レトロトランポゾンは互いに挿入され,複雑な間隔構造を形成します.
これらのレトロエレメントは,Adh1-F領域の60%以上,トウモロコシの核DNAの少なくとも50%を占めています.
特定されたレトロエレメントは,大部分が無傷であり,遺伝子を含むゲノム領域全体に分布しています.

結論:

トウモロコシで例示される複雑な真核ゲノムは,レトロトランポゾンの挿入と増殖によって著しく形作られています.
レトロトランポゾンは,トウモロコシのゲノム内の遺伝子豊富な領域の構造的組織において重要な役割を果たします.
この発見は,ゲノムアーキテクチャにおける反復性DNAの広範囲に及ぶ性質と,遺伝子調節への潜在的な影響を強調しています.

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