FUNCTIONAL GENOMICS IN CLOSE WILD RELATIVES OF ARABIDOPSIS THALIANA

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 防御进化的最优化理论(哈密尔顿等人)2001)，这是我们目前所拥有的理解植物防御和竞争能力同时进化的最佳框架，它预测了防御和竞争之间的权衡，因为国防生产被认为从竞争增长中分流了有限的资源(Herms和Mattson 1992)。我们通过(1)研究防御中的遗传或环境变异对竞争生长的影响，以及(2)研究竞争中的遗传变异对防御表达的影响，对这种进化权衡进行了测试。尽管我们检测到防御成本在没有食草动物的情况下表现为增长放缓，但在竞争环境中没有检测到这些成本(Siemens等人。2002年；西门子等人。2003年)。也就是说，国防生产影响了增长，但不影响竞争力。我们还发现证据表明，防御措施，如硫代葡萄糖苷浓度，有时在更好的竞争对手中更高或更具竞争性地诱导。防御基因的竞争功能可以解释这些结果中的许多。拟南芥的基因组工具使我们能够确定竞争对手是否诱导防御基因，正如人们所预期的那样，防御系统也在竞争中发挥作用。基因组方法还允许对预测的防御和竞争能力之间的权衡进行测试，这可能会加深我们对基因调控的理解(Stearns和Magwene 2003)。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Optimality theory for defense evolution (Hamilton et al. 2001 for overview), currently the best framework we have to understand the simultaneous evolution of defense and competitive ability in plants, predicts a tradeoff between defense and competitiveness because defense production is thought to divert limited resources away from competitive growth (Herms and Mattson 1992). We have tested for this evolutionary tradeoff by (1) studying the effects of genetic or environmental variation in defenses on competitive growth, and by (2) studying the effects of genetic variation in competitiveness on defense expression. Although we have detected costs of defenses manifest as reduced growth in the absence of herbivores, these costs were not detected in competitive environments (Siemens et al. 2002; Siemens et al. 2003). That is, defense production affected growth, but not competitive ability. We have also found evidence that measures of defense, such as glucosinolate concentration, were sometimes higher or competitively induced in better competitors. A competitive function for defensive genes would explain many of these results. The genomic tools of Arabidopsis allow us to determine whether competitors induce defensive genes, as one would expect for defenses that also function in competition. A genomic approach also allows a test for the predicted tradeoff between defense and competitive ability, which may further our understanding of gene regulation (Stearns and Magwene 2003).