Is the regulation of nodulation conserved between species at the cell type level?

氮素是植物体内重要的限制性常量营养元素，对植物的生长发育起着重要的调控作用。通常，能够吸收更多氮（N）并有效利用它的植物具有更高的产量。这就是为什么农民在土壤中施用昂贵且环境昂贵的肥料的原因。豆类，如豌豆或豆类，通常能够与固氮细菌形成共生关系，以便从土壤中的空气中获得否则无法使用的氮。这些根瘤菌被安置在根部的“根瘤”中，在那里N被交换为碳化合物和细菌生态位。如果能够将这种能力带到目前无法做到这一点的农业植物中，这可能导致能够开发出科普不断增长的全球人口所需的氮效率更高的植物。在非豆类农业植物中结瘤也将减少我们对氮肥的依赖，因此将使农业更加环保，并可能更有利可图，特别是对小农场主来说。根瘤形成研究的一个新方向是研究少数几种在根瘤共生中产生根瘤的非豆科植物之一，Parasponia andersonii。最近的研究表明，安氏拟青霉基因组中的结瘤调控基因与模式植物蒺藜苜蓿（Medicago truncatula）高度保守，表明其结瘤的遗传机制也是保守的。通过了解结瘤过程中的保守因素，将扩大对结核的了解，并将有助于今后的工作将结瘤作用推广到其他非豆科农业植物。

Nitrogen is an important limiting macronutrient in plants that regulates plant growth and development. Typically, plants that can take up more nitrogen (N) and utilise it effectively have a higher yield. This is often why farmers apply costly and environmentally expensive fertilisers to their soils. Legumes, such as peas or beans, are unusually able to form a symbiosis with N-fixing bacteria in order to gain otherwise unusable nitrogen from air in soil. These rhizobia are housed in 'nodules' in the roots, where N is exchanged for carbon compounds and a bacterial niche. If the ability to nodulate can be brought to agricultural plants that are not currently able to do so, this could lead to being able to develop the more N-efficient plants that are needed to cope with the ever-increasing global population. Nodulation in non-legume agricultural plants will also reduce our reliance on nitrogen fertilisers and will therefore make the agricultural industry more environmentally friendly and potentially more profitable, particularly for small farm holders. A novel direction in the study of nodulation is to study one of the few non-legumes that produces nodules in rhizobial symbiosis, Parasponia andersonii. Recent evidence shows that nodulation regulatory genes in the genome of P. andersonii are highly conserved with model legumes such as Medicago truncatula, suggesting that the genetic mechanism of nodulation is also conserved. By understanding the conserved elements of the nodulation process, it will broaden the understanding of nodules and will help future work bring nodulation to other non-legume agricultural plants.