北米の灰色の狼におけるメラニズムの分子と進化の歴史
Tovi M Anderson1, Bridgett M vonHoldt, Sophie I Candille
1Departments of Genetics and Pediatrics, Stanford University, Stanford, CA 94305, USA.
Science (New York, N.Y.)
|February 7, 2009
まとめ
オオカミやコヨーテのメラニズムの原因は,飼い犬に由来するKロカス変異である. 犬で選択されたこの特徴は,野生のオオカミの集団に広がり,毛皮の色の多様性に影響を与えました.
科学分野:
- 進化生物学の進化生物学について
- 遺伝学 遺伝学とは
- 動物学 動物学
背景:
- 形態学的多様性は,種の適応の鍵である.
- メラノコルチン1受容体 (Mc1r) 遺伝子変異は,多くの種で色素の変異を引き起こす.
- オオカミのメラニズムは,Mc1r.ではなく,Kロカスに関連している.
研究 の 目的:
- グレーオオカミ (Canis lupus) のメラニズムの原因を調査する.
- メラニスティックKロカス変異の起源と進化史を決定する.
- 家畜の特徴が野生の親戚の多様性にどのように影響するかを理解する.
主な方法:
- オオカミとコヨーテの遺伝子解析.
- Kロカスとそのベータ-デフェンシンタンパク質の調査.
- 選択の分子シグネチャーを調べる.
主要な成果:
- 北米のオオカミのメラニズムを引き起こすKロカス変異は,家畜犬との古代の交配から生じた.
- この変異は,森のオオカミの集団に多く見られ,ポジティブな選択の兆候を示しています.
- この同じ変異は,コヨーテやイタリアのオオカミでもメラニズムを引き起こす.
結論:
- 飼いならされた特徴は,ハイブリッド化によって野生の集団に移すことができます.
- K局所変異は,野生の種の形態学的多様性に対する家畜化の影響を強調しています.
- この研究は,犬類の毛皮の色の変化のためのユニークな進化の経路を明らかにしています.
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