Drosophila melanogaster Transposons: Characterization, Regulation, and Their Role in Genome Evolution

doi:10.12300/j.issn.1674-5817.2025.112

Abstract

Abstract:

Transposable elements (TEs) are mobile DNA sequences in genomes that play key roles in species evolution, genome stability, and gene regulation. Drosophila melanogaster, as a classic model animal with TEs accounting for approximately 20% of its genome, is an ideal model for studying biological characteristics, host defense mechanisms, and functional evolution of TEs, and also provides an important paradigm for understanding mechanisms of TE-related diseases in higher organisms and even humans. This review systematically elucidates the classification and distribution characteristics of TEs in D. melanogaster and their dynamic interactions with host genome, focusing on the host defense system centered on PIWI-interacting RNA (piRNA) pathway. Then, the biological characteristics of key TE families (such as Gypsy, Copia, P-element, and I-element) in D. melanogaster and their dual roles in genomic evolution are analyzed in detail. On the one hand, TE insertions can cause genomic instability, heterozygous sterility, and aging phenotypes, providing a model basis for studying related human diseases (e.g., neurodegenerative diseases, genomic instability syndromes, etc.). On the other hand, their sequences can be co-opted by the host to create novel regulatory elements or functional genes, thereby driving adaptive innovation. Finally, the future research directions of TEs are proposed, including regulation of TE activity by environmental stress, interaction between piRNA pathways and other small RNA systems, as well as regulatory effects of TEs in the occurrence and development of aging and neurodegenerative diseases. The research on TEs in D. melanogaster not only deepens understanding of TE biology, but also provides a key theoretical basis and important inspiration for studying human diseases using experimental animal models, as well as for developing gene therapy and gene editing technologies.

Key words: Drosophila melanogaster, Transposable elements, piRNA, Functional evolution

CLC Number:

Q95-33

WANG Ye,WANG Lu. Drosophila melanogaster Transposons: Characterization, Regulation, and Their Role in Genome Evolution[J]. Laboratory Animal and Comparative Medicine, 2025, 45(6): 676-687. DOI: 10.12300/j.issn.1674-5817.2025.112.

Figures/Tables 3

References 76

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驯化类型 Type of co-option	驯化机制/来源 Mechanism/Source of co-option	功能影响 Functional impact	代表性案例与功能 Representative case & function
调控元件驯化 Regulatory element co-option	TEs调控序列（如启动子、增强子、绝缘子）	改变邻近/宿主基因的表达模式、组织特异性、发育时序或环境响应性	果蝇体色演化：TEs（尤其LTR型）插入影响色素相关基因的调控，驱动体色模式快速变化^[18,27]
编码序列驯化（完全蛋白） Protein-coding sequence co-option (full-length)	TEs完整或近乎完整的编码序列	产生具有细胞功能的全新结构蛋白或酶	PIF-like基因：果蝇属中多次独立驯化自PIF转座酶，形成新的功能基因家族^[20]
编码序列驯化（功能域/模块） Protein-coding sequence co-option (functional domain/module)	TEs编码蛋白的特定结构域	赋予宿主蛋白新功能或参与新细胞过程	Arc/Arc1蛋白（gag域）：来源于逆转录TEs（如Gypsy、Copia）GAG蛋白，形成衣壳样结构，包装自身mRNA，介导神经元-肌肉或神经元间RNA运输，对突触可塑性和记忆维持至关重要^[67-68]
整体元件利用 Holistic element utilization	特定TEs家族的活性或产物	在特定生理或发育过程中被宿主利用	mdg4（Gypsy家族）：在果蝇蛹期变态窗口期激活，通过STING–Relish通路诱导全身性抗病毒免疫状态^[69]

驯化类型 Type of co-option	驯化机制/来源 Mechanism/Source of co-option	功能影响 Functional impact	代表性案例与功能 Representative case & function
调控元件驯化 Regulatory element co-option	TEs调控序列（如启动子、增强子、绝缘子）	改变邻近/宿主基因的表达模式、组织特异性、发育时序或环境响应性	果蝇体色演化：TEs（尤其LTR型）插入影响色素相关基因的调控，驱动体色模式快速变化^[18,27]
编码序列驯化（完全蛋白） Protein-coding sequence co-option (full-length)	TEs完整或近乎完整的编码序列	产生具有细胞功能的全新结构蛋白或酶	PIF-like基因：果蝇属中多次独立驯化自PIF转座酶，形成新的功能基因家族^[20]
编码序列驯化（功能域/模块） Protein-coding sequence co-option (functional domain/module)	TEs编码蛋白的特定结构域	赋予宿主蛋白新功能或参与新细胞过程	Arc/Arc1蛋白（gag域）：来源于逆转录TEs（如Gypsy、Copia）GAG蛋白，形成衣壳样结构，包装自身mRNA，介导神经元-肌肉或神经元间RNA运输，对突触可塑性和记忆维持至关重要^[67-68]
整体元件利用 Holistic element utilization	特定TEs家族的活性或产物	在特定生理或发育过程中被宿主利用	mdg4（Gypsy家族）：在果蝇蛹期变态窗口期激活，通过STING–Relish通路诱导全身性抗病毒免疫状态^[69]