目的 以藥用植物寬葉十萬錯Asystasia gangetica為研究對象，解析其葉綠體基因組結(jié)構(gòu)特征，探究寬葉十萬錯在爵床族中的系統(tǒng)發(fā)育關(guān)系；方法 利用Illumina NovaSeq 6000測序平臺對寬葉十萬錯葉綠體基因組進(jìn)行測序，對其進(jìn)行組裝、注釋和特征序列分析，并基于34種爵床族物種構(gòu)建系統(tǒng)發(fā)育樹。結(jié)果 寬葉十萬錯葉綠體基因組為典型的四分體結(jié)構(gòu)，總序列長度為150 307 bp，包括一個大單拷貝區(qū)（LSC，82 332 bp），一個小單拷貝區(qū)（SSC，17 425 bp）和一對反向重復(fù)區(qū)（IRs，25 275 bp）；寬葉十萬錯葉綠體基因組共注釋到光合作用基因、自我復(fù)制基因、其他基因和未知功能基因4類共133個基因，包括88個蛋白編碼基因，37個tRNA基因和8個rRNA基因；寬葉十萬錯葉綠體基因組共檢測到34個SSR位點(diǎn)，SSR類型以A/T為主，通過REPuter軟件共檢測到33個長重復(fù)序列；IR區(qū)邊界分析表明，寬葉十萬錯比其他屬物種保守，邊界區(qū)域變異??；基于8個屬8個物種全葉綠體基因組比較分析可知，基因間隔區(qū)atpH-atpI、petN-trnD-GUC、rps4-trnT-UGU、trnF-GAA-ndhJ等的變異大于編碼區(qū)；寬葉十萬錯密碼子偏好性分析表明，甘氨酸是寬葉十萬錯使用頻次最高的氨基酸，以A或U結(jié)尾的密碼子是寬葉十萬錯葉綠體基因組的偏好性密碼子；ENC、PR2和中性繪圖分析表明，自然選擇是影響寬葉十萬錯密碼子偏好性的主要原因；選擇壓力分析表明，有9個基因受到正選擇，對寬葉十萬錯及其近緣屬物種適應(yīng)性進(jìn)化具有重要作用；系統(tǒng)發(fā)育分析表明，寬葉十萬錯所在的十萬錯屬和鉤粉草屬形成姊妹類群，親緣關(guān)系最近，并具有較高的支持率，共同歸為彩葉木亞族。結(jié)論 對寬葉十萬錯葉綠體基因組結(jié)構(gòu)進(jìn)行了解析，并探討了爵床族物種系統(tǒng)發(fā)育關(guān)系，豐富了爵床族藥用植物遺傳資源，為爵床族的物種分類提供了參考。

Objective To analyze the structural features of the chloroplast genome in medicinal plant Asystasia gangetica and explore its phylogenetic relationships in the tribe Justiceae. Methods The chloroplast genome sequence of A. gangetica was obtained by sequencing with Illumina NovaSeq 6000, and assembled, annotated and analyzed the characteristic sequences of the genome. A phylogenetic tree was constructed based on 34 species of the tribe Justiceae. Results The chloroplast genome of A. gangetica exhibits a typical tetrad structure with a length of 150 307 bp, including a large single-copy region (LSC, 82 332 bp), a small single-copy region (SSC, 17 425 bp), and a pair of inverted repeat regions (IRs, 25 275 bp). The chloroplast genome of A. gangetica has been annotated with 133 genes in four categories: photosynthesis genes, self-replication genes, other genes and unknown functional genes, comprising 88 protein-coding genes, 37 tRNA genes and eight rRNA genes. A total of 34 SSR loci were detected in the chloroplast genome of A. gangetica, with A/T being the predominant SSR type; REPuter software identified 33 long repeat sequences; Analysis of IR boundaries indicated that A. gangetica was more conservative than other species, with minimal variation in the boundary region. Based on the comparative analysis of complete chloroplast genomes of eight species from eight genera, it can be concluded that the variation rates of atpH-atpI, petN-trnD-GUC, rps4-trnT-UGU, trnF-GAA-ndhJ etc in gene spacer regions were the highest. The codon usage bias analysis of A. gangetica indicated that glycine was the most frequently used amino acid in A. gangetica, and codons ending in A or U had a strong impact on codon perference. The ENC, PR2, and neutrality plot analyses indicated that natural selection was the primary factor influencing codon preference in A. gangetica. The selective pressure analysis revealed that nine genes were under positive selection, playing a crucial role in the adaptive evolution of A. gangetica and its closely related species. Phylogenetic analysis indicated that Asystasia and Pseuderanthemum form a sister group, with the closest genetic relationship and high support value, and were collectively classified as the subtribe Graptophyllinae. Conclusion This study analyzes the chloroplast genome structure of A. gangetica and explores the phylogenetic relationships within the tribe Justiceae, with view to enriching the genetic resources of medicinal plant in the tribe Justiceae and providing a reference for species classification.

R286.12

國家自然科學(xué)基金項目（32100168）;福建省自然科學(xué)基金項目（2021J05061）;福建中醫(yī)藥大學(xué)基礎(chǔ)類學(xué)科科研提升計劃項目（XJC2023008）;福建中醫(yī)藥大學(xué)校管課題（X2023025）;福建中醫(yī)藥大學(xué)高層次人才科研啟動資金項目（X2020012-人才）