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.
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widely popular It's generally tough to a spontaneous mutation deletion grocery store
马克吐温称之为“人类所知的最美味的水果。”这就是毛叶番荔枝。假如你从未听说过这个名字，那也情有可原。这种水果的特性让它不能街知巷闻——它甜美的白果肉里有许多巨大的种子。 但现在西班牙的科学家和加利福尼亚大学的达维斯发现了让毛叶番荔枝和同种水果去籽的方法。他们在《美国科学院学报》上刊登了研究成果。 培育无籽水果通常是很困难的——香蕉和橙子是罕见的成功例子。无籽水果的繁殖通常都会因果实无法发育至人们所需而失败。但科学家找到了一个自发变异，这种变异可以使毛叶番荔枝的亲戚——番荔枝——去籽。他们将番荔枝的基因组和实验中经常使用的无籽突变植物——拟南芥——的基因组进行比较。 他们发现两种水果都有某段基因缺失。研究人员表示这是第一次发现无子果实的基因。如果他们找到方法锁定毛叶番荔枝中的无籽基因，就有可能让马克吐温和许多人最爱的水果出现在你家附近的杂货店里了。