免疫グロブリン遺伝子の異常な位置でのタンパク質合成の開始?

O Smithies, M D Poulik

Science (New York, N.Y.)

|January 14, 1972

まとめ

尿中に存在するβ2−マイクログローブリンのアミノ酸配列は,免疫グロブリン重鎖との関係を示している. これは,その遺伝子が免疫グロブリン遺伝子から進化した可能性があることを示唆しています.

科学分野:

バイオケミストリーバイオケミストリー
免疫学免疫学とは
分子生物学は分子生物学である.

背景:

ベータ(2) - マイクログローブリン (B2M) は,尿を含む体液に含まれるタンパク質です.
その正確な生物学的機能と進化的起源は,現在進行中の研究分野です.

研究の目的:

尿中のベータ(2) - マイクログローブリンのアミノ酸配列を部分的に決定する.
ベータ(2) - マイクログローブリンと免疫グロブリン遺伝子の間の潜在的な進化的関係を調査する.

主な方法:

精製された尿中のβ-ミクログローブリンの部分的アミノ酸配列解析.
既知の免疫グロブリン重鎖定数領域との比較シーケンス分析.

主要な成果:

泌尿中のβ(2) -マイクログローブリンの決定されたアミノ酸配列は,IgG免疫グロブリン重鎖の常数領域と有意な同質性を示しています.
ベータ(2) -マイクログローブリンは,明らかな病理学がない個体において存在することが確認されています.

結論:

この発見は,ベータ2マイクログローブリン遺伝子が,免疫グロブリン遺伝子から進化した可能性があることを示唆している.
ポリペプチド合成のための異常な位置のスタートシグナルが,進化の起源を説明するかもしれない.

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