1
|
Walt HK, Ahn SJ, Hoffmann FG. Horizontally transferred glycoside hydrolase 26 may aid hemipteran insects in plant tissue digestion. Mol Phylogenet Evol 2024; 198:108134. [PMID: 38901473 DOI: 10.1016/j.ympev.2024.108134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 05/28/2024] [Accepted: 06/15/2024] [Indexed: 06/22/2024]
Abstract
Glycoside hydrolases are enzymes that break down complex carbohydrates into simple sugars by catalyzing the hydrolysis of glycosidic bonds. There have been multiple instances of adaptive horizontal gene transfer of genes belonging to various glycoside hydrolase families from microbes to insects, as glycoside hydrolases can metabolize constituents of the carbohydrate-rich plant cell wall. In this study, we characterize the horizontal transfer of a gene from the glycoside hydrolase family 26 (GH26) from bacteria to insects of the order Hemiptera. Our phylogenies trace the horizontal gene transfer to the common ancestor of the superfamilies Pentatomoidea and Lygaeoidea, which include stink bugs and seed bugs. After horizontal transfer, the gene was assimilated into the insect genome as indicated by the gain of an intron, and a eukaryotic signal peptide. Subsequently, the gene has undergone independent losses and expansions in copy number in multiple lineages, suggesting an adaptive role of GH26s in some insects. Finally, we measured tissue-level gene expression of multiple stink bugs and the large milkweed bug using publicly available RNA-seq datasets. We found that the GH26 genes are highly expressed in tissues associated with plant digestion, especially in the principal salivary glands of the stink bugs. Our results are consistent with the hypothesis that this horizontally transferred GH26 was co-opted by the insect to aid in plant tissue digestion and that this HGT event was likely adaptive.
Collapse
Affiliation(s)
- Hunter K Walt
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS 39762, USA
| | - Seung-Joon Ahn
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS 39762, USA
| | - Federico G Hoffmann
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS 39762, USA; Institute for Genomics, Biotechnology and Biocomputing, Mississippi State University, Mississippi State, MS 39762, USA.
| |
Collapse
|
2
|
Sylvester T, Adams R, Hunter WB, Li X, Rivera-Marchand B, Shen R, Shin NR, McKenna DD. The genome of the invasive and broadly polyphagous Diaprepes root weevil, Diaprepes abbreviatus (Coleoptera), reveals an arsenal of putative polysaccharide-degrading enzymes. J Hered 2024; 115:94-102. [PMID: 37878740 DOI: 10.1093/jhered/esad064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 09/14/2023] [Accepted: 10/23/2023] [Indexed: 10/27/2023] Open
Abstract
The Diaprepes root weevil (DRW), Diaprepes abbreviatus, is a broadly polyphagous invasive pest of agriculture in the southern United States and the Caribbean. Its genome was sequenced, assembled, and annotated to study genomic correlates of specialized plant-feeding and invasiveness and to facilitate the development of new methods for DRW control. The 1.69 Gb D. abbreviatus genome assembly was distributed across 653 contigs, with an N50 of 7.8 Mb and the largest contig of 62 Mb. Most of the genome was comprised of repetitive sequences, with 66.17% in transposable elements, 5.75% in macrosatellites, and 2.06% in microsatellites. Most expected orthologous genes were present and fully assembled, with 99.5% of BUSCO genes present and 1.5% duplicated. One hundred and nine contigs (27.19 Mb) were identified as putative fragments of the X and Y sex chromosomes, and homology assessment with other beetle X chromosomes indicated a possible sex chromosome turnover event. Genome annotation identified 18,412 genes, including 43 putative horizontally transferred (HT) loci. Notably, 258 genes were identified from gene families known to encode plant cell wall degrading enzymes and invertases, including carbohydrate esterases, polysaccharide lyases, and glycoside hydrolases (GH). GH genes were unusually numerous, with 239 putative genes representing 19 GH families. Interestingly, several other beetle species with large numbers of GH genes are (like D. abbreviatus) successful invasive pests of agriculture or forestry.
Collapse
Affiliation(s)
- Terrence Sylvester
- Department of Biological Sciences, University of Memphis, Memphis, TN 38152, United States
- Center for Biodiversity Research, University of Memphis, Memphis, TN 38152, United States
| | - Richard Adams
- Department of Entomology and Plant Pathology, University of Arkansas, Fayetteville, AR, United States
- Agricultural Statistics Laboratory, University of Arkansas, Fayetteville, AR, United States
| | - Wayne B Hunter
- USDA, ARS, U. S. Horticultural Research Laboratory, Fort Pierce, FL 34945, United States
| | - Xuankun Li
- Department of Biological Sciences, University of Memphis, Memphis, TN 38152, United States
- Center for Biodiversity Research, University of Memphis, Memphis, TN 38152, United States
- Department of Entomology, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Bert Rivera-Marchand
- Office of Academic Affairs, Polk State College, Lakeland Campus, Lakeland, FL, 33803, United States
| | - Rongrong Shen
- Department of Biological Sciences, University of Memphis, Memphis, TN 38152, United States
- Center for Biodiversity Research, University of Memphis, Memphis, TN 38152, United States
| | - Na Ra Shin
- Department of Biological Sciences, University of Memphis, Memphis, TN 38152, United States
- Center for Biodiversity Research, University of Memphis, Memphis, TN 38152, United States
| | - Duane D McKenna
- Department of Biological Sciences, University of Memphis, Memphis, TN 38152, United States
- Center for Biodiversity Research, University of Memphis, Memphis, TN 38152, United States
| |
Collapse
|
3
|
Körnig J, Ortizo K, Sporer T, Yang ZL, Beran F. Different myrosinases activate sequestered glucosinolates in larvae and adults of the horseradish flea beetle. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2023; 163:104040. [PMID: 37995833 DOI: 10.1016/j.ibmb.2023.104040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 11/09/2023] [Accepted: 11/13/2023] [Indexed: 11/25/2023]
Abstract
β-Glucosidases play an important role in the chemical defense of many insects by hydrolyzing and thereby activating glucosylated pro-toxins that are either synthesized de novo or sequestered from the insect's diet. The horseradish flea beetle, Phyllotreta armoraciae, sequesters pro-toxic glucosinolates from its brassicaceous host plants and possesses endogenous β-thioglucosidase enzymes, known as myrosinases, for glucosinolate activation. Here, we identify three myrosinase genes in P. armoraciae (PaMyr) with distinct expression patterns during beetle ontogeny. By using RNA interference, we demonstrate that PaMyr1 is responsible for myrosinase activity in adults, whereas PaMyr2 is responsible for myrosinase activity in larvae. Compared to PaMyr1 and PaMyr2, PaMyr3 was only weakly expressed in our laboratory population, but may contribute to myrosinase activity in larvae. Silencing of PaMyr2 resulted in lower larval survival in a predation experiment and also reduced the breakdown of sequestered glucosinolates in uninjured larvae. This suggests that PaMyr2 is involved in both activated defense and the endogenous turnover of sequestered glucosinolates in P. armoraciae larvae. In activity assays with recombinant enzymes, PaMyr1 and PaMyr2 preferred different glucosinolates as substrates, which was consistent with the enzyme activities in crude protein extracts from adults and larvae, respectively. These differences were unexpected because larvae and adults sequester the same glucosinolates. Possible reasons for different myrosinase activities in Phyllotreta larvae and adults are discussed.
Collapse
Affiliation(s)
- Johannes Körnig
- Research Group Sequestration and Detoxification in Insects, Max Planck Institute for Chemical Ecology, Jena, Germany; Department Insect Symbiosis, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Kris Ortizo
- Research Group Sequestration and Detoxification in Insects, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Theresa Sporer
- Research Group Sequestration and Detoxification in Insects, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Zhi-Ling Yang
- Research Group Sequestration and Detoxification in Insects, Max Planck Institute for Chemical Ecology, Jena, Germany; Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Yunnan, China
| | - Franziska Beran
- Research Group Sequestration and Detoxification in Insects, Max Planck Institute for Chemical Ecology, Jena, Germany; Department Insect Symbiosis, Max Planck Institute for Chemical Ecology, Jena, Germany; Population Ecology Group, Friedrich-Schiller Universität Jena, Jena, Germany.
| |
Collapse
|