Mark Twain called it “the most delicious fruit known to men.” He was talking about the cherimoya. If you never heard of it, there’s good reason. It has a feature that has prevented it from becoming ____1____—numerous big seeds fill its sweet white flesh.
But now scientists in Spain and at the University of California, Davis, have found the key to making the cherimoya and related fruits seedless. They published their research in the Proceedings of the National Academy of Sciences.
____2____develop a seedless fruit—bananas and oranges are rare successes. Breeding for seedlessness usually fails to produce the fully developed fruit consumers demand. But the scientists found ____3____that causes seedlessness in a cherimoya relative, the sugar apple. They compared its genome to that of a seedless mutant of a plant called Arabidopsis that’s used in a lot of research.
In both cases, they found a ____4____of one particular gene. The researchers say this is the first time a gene for seedlessness has been determined. If they can find a way to knock out that gene in the cherimoya, it could bring Mark Twain’s favorite fruit, and many others, to a ____5____near you.
【視聽版科學小組榮譽出品】
widely popular It's generally tough to a spontaneous mutation deletion grocery store
馬克吐溫稱之為“人類所知的最美味的水果。”這就是毛葉番荔枝。假如你從未聽說過這個名字，那也情有可原。這種水果的特性讓它不能街知巷聞——它甜美的白果肉里有許多巨大的種子。 但現(xiàn)在西班牙的科學家和加利福尼亞大學的達維斯發(fā)現(xiàn)了讓毛葉番荔枝和同種水果去籽的方法。他們在《美國科學院學報》上刊登了研究成果。 培育無籽水果通常是很困難的——香蕉和橙子是罕見的成功例子。無籽水果的繁殖通常都會因果實無法發(fā)育至人們所需而失敗。但科學家找到了一個自發(fā)變異，這種變異可以使毛葉番荔枝的親戚——番荔枝——去籽。他們將番荔枝的基因組和實驗中經(jīng)常使用的無籽突變植物——擬南芥——的基因組進行比較。 他們發(fā)現(xiàn)兩種水果都有某段基因缺失。研究人員表示這是第一次發(fā)現(xiàn)無子果實的基因。如果他們找到方法鎖定毛葉番荔枝中的無籽基因，就有可能讓馬克吐溫和許多人最愛的水果出現(xiàn)在你家附近的雜貨店里了。