Institute of Pathogens and Vectors, Yunnan Provincial Key Laboratory for Zoonosis Control and Prevention, Dali University, Dali, 671000, Yunnan, China.
Sci Rep. 2024 Aug 6;14(1):18179. doi: 10.1038/s41598-024-69203-y.
Fleas are the most important insect vectors that parasitize warm-blooded animals and are known vectors of zoonotic pathogens. A recent study showed that Stenoponia polyspina parasitizing Eospalax baileyi in Zoige County have carried Bartonella spp. and Spotted fever group Rickettsia (SFGR). Accurate identification and differentiation of fleas are essential for prevention and control of zoonotic pathogens. To understand phylogenetic relationship of the subfamily Stenoponiinae, we described morphological characteristics of S. polyspina and sequenced its mitogenome with 14,933 bp in size and high A + T content (~ 79%). The S. polyspina mitogenome retained the ancestral pattern of mitochondrial gene arrangement of arthropods without rearrangement. The start codons of 13 protein-coding genes (PCGs) are traditional ATN and the stop codons are TAA or TAG. Anticodon loops of all tRNA genes were 7 bp except for trnL and trnD had anticodon loops with 9 bp and the abnormal anticodon loops may be associated with frameshifting mutation. Genetic distance and Ka/Ks ratios indicated that all 13 PCGs of S. polyspina were subjected to purifying selection, with cox1 at the slowest rate and atp8 at the fastest rate. The mitogenomes of 24 species representing 7 families in the order Siphonaptera were selected to reconstruct phylogenetic tree based on concatenated nucleotide sequences of two datasets (PCGRNA matrix and PCG12RNA matrix) using Bayesian inference (BI) and Maximum likelihood (ML) methods. Phylogenetic tree supported that the superfamilies Ceratophylloidea, Vermipsylloidea, Pulicoidea were monophyletic and the superfamily Hystrichopsylloidea was paraphyletic. The family Ctenophthalmidae was monophyletic in PCGRNA-ML (codon partition) and paraphyletic in the remain trees. S. polyspina belongs to the subfamily Stenoponiinae was closely more related to the subfamily Rhadinopsyllinae. This paper explored phylogenetic position of diverse clades within the order Siphonaptera based on morphological and mitogenome data of S. polyspina. Our research enriched NCBI database of the order Siphonaptera.
跳蚤是寄生在温血动物身上最重要的昆虫媒介，已知是人畜共患病病原体的媒介。最近的一项研究表明，在若尔盖县寄生在 Eospalax baileyi 上的 Stenoponia polyspina 携带了巴尔通体属和斑点热群立克次体（SFGR）。准确识别和区分跳蚤对于预防和控制人畜共患病病原体至关重要。为了了解 Stenoponiinae 亚科的系统发育关系，我们描述了 S. polyspina 的形态特征，并对其线粒体基因组进行了测序，大小为 14933bp，A+T 含量较高（约 79%）。S. polyspina 线粒体基因组保留了节肢动物线粒体基因排列的祖先模式，没有重排。13 个蛋白质编码基因（PCGs）的起始密码子为传统的 ATN，终止密码子为 TAA 或 TAG。除了 trnL 和 trnD 的反密码子环为 9bp 外，所有 tRNA 基因的反密码子环均为 7bp，异常的反密码子环可能与移码突变有关。遗传距离和 Ka/Ks 比值表明，S. polyspina 的 13 个 PCGs 都受到了纯化选择，cox1 最慢，atp8 最快。选择了鳞翅目目 7 科 24 种代表种的线粒体基因组，基于两个数据集（PCGRNA 矩阵和 PCG12RNA 矩阵）的核苷酸序列，采用贝叶斯推断（BI）和最大似然（ML）方法构建系统发育树。系统发育树支持 Ceratophylloidea、Vermipsylloidea、Pulicoidea 超科是单系的，Hystrichopsylloidea 超科是并系的。Ctenophthalmidae 科在 PCGRNA-ML（密码子分区）中是单系的，而在其余树中是并系的。S. polyspina 属于 Stenoponiinae 亚科，与 Rhadinopsyllinae 亚科的关系更为密切。本文基于 S. polyspina 的形态学和线粒体基因组数据，探讨了鳞翅目目内不同分支的系统发育位置。我们的研究丰富了鳞翅目目 NCBI 数据库。
