摘要 :
It is becoming increasingly vital to improve the yield of seed crops to feed an expanding population and, more recently, for biofuel production. One strategy to increase the yield is to increase the seed size, provided that there ...
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It is becoming increasingly vital to improve the yield of seed crops to feed an expanding population and, more recently, for biofuel production. One strategy to increase the yield is to increase the seed size, provided that there is not a concomitant decrease in seed number. In a previous study, we described a mutant in the AUXIN RESPONSE FACTOR 2 (ARF2) gene which produced extra cells in the seed coat and, subsequently, enlarged seeds. However, arf2 mutant plants also show severely reduced self-fertility caused, in part, by over-elongated sepals that prevent flower opening. As a low seed set increases individual seed size, a meaningful comparison of the yield in arf2 and wild-type plants could not be conducted. In this study, we show that targeted expression of wild-type ARF2 in the sepals and petals of arf2-9 mutant flowers restores flower opening and dramatically increases seed set. The restored plants retain both enlarged integuments and increased seed size, reinforcing previous evidence that arf2 mutations increase seed weight through their effect on integuments and not only via reduced fertility. We also show that the measurement of the harvest index in Arabidopsis is useful in assessing the impact of introduced traits on the yield.
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摘要 :
Malignant rhabdoid tumor (MRT) is a rare tumor occurring mostly in kidneys and central nervous system (CNS). Its prognosis is not good. Occasionally, MRTs are diagnosed at or immediately after birth. A female neonate presented wit...
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Malignant rhabdoid tumor (MRT) is a rare tumor occurring mostly in kidneys and central nervous system (CNS). Its prognosis is not good. Occasionally, MRTs are diagnosed at or immediately after birth. A female neonate presented with MRT in the chest wall, axilla, right elbow, and bone marrow. Chest wall lesion was resected completely. Although the masses in axilla and bone marrow responded rapidly to chemotherapy, the elbow lesion increased in size. Despite intense treatment, the tumor relapsed in lungs and the patient died 12 months after diagnosis. Review of the literature showed twenty additional congenital MRTs arising from sites outside of the kidney and central nervous system were published in the literature. Eighteen patients had disseminated disease at diagnosis. The median overall survival time for all (n = 21) patients was 2.0 months (0-24 months). The only patient who survived had a localized tumor at initial diagnosis. Congenital, extrarenal, non-CNS MRTs are aggressive tumors with poor outcome.
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