ホメオティック遺伝子は,ドロソフィラメソダームのパターンの1つの側面を自律的に指定します

S Greig¹, M Akam

¹Wellcome/CRC Institute, Cambridge, UK.

Nature

|April 15, 1993

まとめ

昆虫の内皮は自律的に発達する. メソダームの腹部-Aホメオティック遺伝子の胎外発現は,胸筋の前駆細胞を腹部アイデンティティに変換しました.

科学分野:

発達生物学発達生物学とは
遺伝学遺伝学とは
昆虫生物学昆虫生物学とは

背景:

昆虫のメソドームは素朴な組織であり,外皮から発するパターニングシグナルがあると考えられていた.
以前の研究では,ホメオティック遺伝子は,セグメント特異的な発現と,表皮に対する筋肉に対する突然変異の明確な影響によって証明された,いくつかのメソダーマのパターンを自律的に指定する可能性があることが示唆されました.

研究の目的:

ホメオティックな遺伝子が昆虫の中皮を自律的にパターン化できるかどうかを直接調査する.
メソダーマにおけるホメオティック遺伝子のエクトピック発現が,エクトダーマのシグナルとは無関係にメソダーマ細胞の運命を変化させることができるかどうかを判断する.

主な方法:

ドロソフィラのメソダーム内におけるホメオティックな遺伝子のエクトピック発現.
実験操作後の成人の筋肉前駆細胞パターンの分析.

主要な成果:

ホメオティック遺伝子の腹部-Aをメソダームでエクトピカルに発現させることで,胸筋前駆細胞が腹部アイデンティティに変換されました.
この変換は,上層のエクトダーマのホメオティック遺伝子の発現を変化させることなく発生した.

結論:

ホメオティック遺伝子は,メソダーマの細胞運命を自律的に指定することができ,メソダーマのパターニングにおけるエクトダーマの優位性に関する一般的な見解に異議を唱えます.
メソデルマは,ホメオティック遺伝子の活動に影響を受ける内在的なパターニング能力を有しており,セグメント特有の発達に貢献しています.

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