Galloway G L, Malmberg R L, Price R A
Department of Botany, University of Georgia at Athens 30602, USA.
Mol Biol Evol. 1998 Oct;15(10):1312-20. doi: 10.1093/oxfordjournals.molbev.a025859.
Arginine decarboxylase (ADC) is an important enzyme in the production of putrescine and polyamines in plants. It is encoded by a single or low-copy nuclear gene that lacks introns in sequences studied to date. The rate of Adc amino acid sequence evolution is similar to that of ndhF for the angiosperm family studied. Highly conserved regions provide several target sites for PCR priming and sequencing and aid in nucleotide and amino acid sequence alignment across a range of taxonomic levels, while a variable region provides an increased number of potentially informative characters relative to ndhF for the taxa surveyed. The utility of the Adc gene in plant molecular systematic studies is demonstrated by analysis of its partial nucleotide sequences obtained from 13 representatives of Brassicaceae and 3 outgroup taxa, 2 from the mustard oil clade (order Capparales) and 1 from the related order Malvales. Two copies of the Adc gene, Adc1 and Adc2, are found in all members of the Brassicaceae studied to data except the basal genus Aethionema. The resulting Adc gene tree provides robust phylogenetic data regarding relationships within the complex mustard family, as well as independent support for proposed tribal realignments based on other molecular data sets such as those from chloroplast DNA.
精氨酸脱羧酶（ADC）是植物中腐胺和多胺产生过程中的一种重要酶。它由一个单拷贝或低拷贝的核基因编码，在迄今为止研究的序列中没有内含子。在所研究的被子植物科中，Adc氨基酸序列的进化速率与ndhF的相似。高度保守的区域为PCR引物设计和测序提供了几个靶点，并有助于在一系列分类水平上进行核苷酸和氨基酸序列比对，而一个可变区域相对于所调查的分类群的ndhF提供了更多潜在的信息特征。通过分析从十字花科的13个代表种以及3个外类群分类单元（2个来自芥子油分支（白花菜目），1个来自相关的锦葵目）获得的Adc基因部分核苷酸序列，证明了Adc基因在植物分子系统学研究中的实用性。在所研究的十字花科所有成员中，除了基部属岩芥菜属外，都发现了两个Adc基因拷贝，即Adc1和Adc2。由此产生的Adc基因树提供了关于复杂十字花科内部关系的可靠系统发育数据，以及基于其他分子数据集（如来自叶绿体DNA的数据集）提出的族重新排列的独立支持。
