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Zhao Y, Luo X, Hu J, Panga MJ, Appiah C, Du Z, Zhu L, Retyunskiy V, Gao X, Ma B, Zhang Q. Syringin alleviates bisphenol A-induced spermatogenic defects and testicular injury by suppressing oxidative stress and inflammation in male zebrafish. Int Immunopharmacol 2024; 131:111830. [PMID: 38520788 DOI: 10.1016/j.intimp.2024.111830] [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: 11/26/2023] [Revised: 02/21/2024] [Accepted: 03/06/2024] [Indexed: 03/25/2024]
Abstract
Syringin (SRG) is a bioactive principle possessing extensive activities including scavenging of free radicals, inhibition of apoptosis, and anti-inflammatory properties. However, its effects on spermatogenic defects and testicular injury as well as the underlying mechanisms are still unclear. This study aims to investigate the protective effect of SRG on testis damage in zebrafish and explore its potential molecular events. Zebrafish testicular injury was induced by exposure to bisphenol A (BPA) (3000 μg/L) for two weeks. Fish were treated with intraperitoneal injection of SRG at different doses (5 and 50 mg/kg bodyweight) for two more weeks under BPA induction. Subsequently, the testis and sperm were collected for morphological, histological, biochemical and gene expression examination. It was found that the administration of SRG resulted in a significant protection from BPA-caused impact on sperm concentration, morphology, motility, fertility rate, testosterone level, spermatogenic dysfunction and resulted in increased apoptotic and reactive oxygen species' levels. Furthermore, testicular transcriptional profiling alterations revealed that the regulation of inflammatory response and oxidative stress were generally enriched in differentially expressed genes (DEGs) after SRG treatment. Additionally, it was identified that SRG prevented BPA-induced zebrafish testis injury through upregulation of fn1a, krt17, fabp10a, serpina1l and ctss2. These results indicate that SRG alleviated spermatogenic defects and testicular injury by suppressing oxidative stress and inflammation in male zebrafish.
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Affiliation(s)
- Ye Zhao
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, China.
| | - Xu Luo
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, China
| | - Jinyuan Hu
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, China
| | - Mogellah John Panga
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, China
| | - Clara Appiah
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, China
| | - Zhanxiang Du
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, China
| | - Lin Zhu
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, China
| | - Vladimir Retyunskiy
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, China
| | - Xing Gao
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, China
| | - Bo Ma
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, China.
| | - Qi Zhang
- School of Food Engineering, Nanjing Tech University, Nanjing 211816, China.
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Leipart V, Montserrat-Canals M, Cunha ES, Luecke H, Herrero-Galán E, Halskau Ø, Amdam GV. Structure prediction of honey bee vitellogenin: a multi-domain protein important for insect immunity. FEBS Open Bio 2021; 12:51-70. [PMID: 34665931 PMCID: PMC8727950 DOI: 10.1002/2211-5463.13316] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 09/27/2021] [Accepted: 10/18/2021] [Indexed: 11/28/2022] Open
Abstract
Vitellogenin (Vg) has been implicated as a central protein in the immunity of egg‐laying animals. Studies on a diverse set of species suggest that Vg supports health and longevity through binding to pathogens. Specific studies of honey bees (Apis mellifera) further indicate that the vitellogenin (vg) gene undergoes selection driven by local pathogen pressures. Determining the complete 3D structure of full‐length Vg (flVg) protein will provide insights regarding the structure–function relationships underlying allelic variation. Honey bee Vg has been described in terms of function, and two subdomains have been structurally described, while information about the other domains is lacking. Here, we present a structure prediction, restrained by experimental data, of flVg from honey bees. To achieve this, we performed homology modeling and used AlphaFold before using a negative‐stain electron microscopy map to restrict, orient, and validate our 3D model. Our approach identified a highly conserved Ca2+‐ion‐binding site in a von Willebrand factor domain that might be central to Vg function. Thereafter, we used rigid‐body fitting to predict the relative position of high‐resolution domains in a flVg model. This mapping represents the first experimentally validated full‐length protein model of a Vg protein and is thus relevant for understanding Vg in numerous species. Our results are also specifically relevant to honey bee health, which is a topic of global concern due to rapidly declining pollinator numbers.
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Affiliation(s)
- Vilde Leipart
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Aas, Norway
| | | | - Eva S Cunha
- Norwegian Center for Molecular Medicine, University of Oslo, Norway
| | - Hartmut Luecke
- Department of Physiology and Biophysics, University of California, Irvine, CA, USA
| | - Elías Herrero-Galán
- Department of Structure of Macromolecules, Centro Nacional de Biotecnología (CNB-CSIC), Madrid, Spain
| | - Øyvind Halskau
- Department of Biological Sciences, University of Bergen, Norway
| | - Gro V Amdam
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Aas, Norway.,School of Life Sciences, Arizona State University, Tempe, AZ, United States
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Lindsay WR, Friesen CR, Sihlbom C, Bergström J, Berger E, Wilson MR, Olsson M. Vitellogenin offsets oxidative costs of reproduction in female painted dragon lizards. J Exp Biol 2020; 223:jeb221630. [PMID: 32393548 DOI: 10.1242/jeb.221630] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 05/05/2020] [Indexed: 12/18/2022]
Abstract
Vitellogenesis ('yolking' of follicles) is a bioenergetically costly stage of reproduction requiring enlargement of the liver to produce vitellogenin (VTG) yolk precursor proteins, which are transported and deposited at the ovary. VTG may, however, serve non-nutritive anti-oxidant functions, a hypothesis supported by empirical work on aging and other life-history transitions in several taxa. We test this hypothesis in female painted dragon lizards (Ctenophorus pictus) by examining covariation in VTG with the ovarian cycle, and relative to reactive oxygen species (ROS) including baseline superoxide (bSO). Plasma VTG decreased prior to ovulation, when VTG is deposited into follicles. VTG, however, remained elevated post-ovulation when no longer necessary for yolk provisioning and was unrelated to reproductive investment. Instead, VTG was strongly and positively predicted by prior bSO. ROS, in turn, was negatively predicted by prior VTG, while simultaneously sampled VTG was a positive predictor. These findings are consistent with the hypothesis that VTG functions as an anti-oxidant to counteract oxidative stress associated with vitellogenesis. The relationship between bSO and VTG was strongest in post-ovulatory females, indicating that its function may be largely anti-oxidant at this time. In conclusion, VTG may be under selection to offset oxidative costs of reproduction in egg-producing species.
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Affiliation(s)
- Willow R Lindsay
- Department of Biological and Environmental Sciences, University of Gothenburg, SE 405 30 Gothenburg, Sweden
| | - Christopher R Friesen
- School of Chemistry and Molecular Bioscience and Molecular Horizons Research Institute, The University of Wollongong, Wollongong, NSW 2522, Australia
| | - Carina Sihlbom
- Proteomics Core Facility of Sahlgrenska Academy, University of Gothenburg, SE 405 30 Gothenburg, Sweden
| | - Jörgen Bergström
- Proteomics Core Facility of Sahlgrenska Academy, University of Gothenburg, SE 405 30 Gothenburg, Sweden
| | - Evelin Berger
- Proteomics Core Facility of Sahlgrenska Academy, University of Gothenburg, SE 405 30 Gothenburg, Sweden
| | - Mark R Wilson
- School of Chemistry and Molecular Bioscience and Molecular Horizons Research Institute, The University of Wollongong, Wollongong, NSW 2522, Australia
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Mats Olsson
- Department of Biological and Environmental Sciences, University of Gothenburg, SE 405 30 Gothenburg, Sweden
- School of Chemistry and Molecular Bioscience and Molecular Horizons Research Institute, The University of Wollongong, Wollongong, NSW 2522, Australia
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Shen Y, Chen YZ, Lou YH, Zhang CX. Vitellogenin and Vitellogenin-Like Genes in the Brown Planthopper. Front Physiol 2019; 10:1181. [PMID: 31620015 PMCID: PMC6759490 DOI: 10.3389/fphys.2019.01181] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Accepted: 09/02/2019] [Indexed: 12/14/2022] Open
Abstract
Vitellogenin (Vg) is precursor of vitellin. Here, we identified a Vg (NlVg) and two Vg-likes (NlVg-like1 and NlVg-like2) in the brown planthopper, Nilaparvata lugens. Phylogenetic analyses showed that NlVg-like1 and NlVg-like2 are not clustered with the conventional insect Vgs associated with vitellogenesis. Temporo-spatial expression analyses showed that the NlVg and NlVg-like2 transcript levels increased significantly 24 h after emergence and were primarily expressed in female adults. However, NlVg-like1 was expressed during all stages, and in both genders. Tissue-specific analyses showed that all three genes were most highly expressed in the fat body. The injection of double-stranded RNA targeting NlVg showed that NlVg is essential not only for oocyte development but also for nymph development. The knockdown of NlVg-like1 in female adults resulted in failure to hatch or death before eggshell emergence in 18% of offspring embryos, suggesting that NlVg-like1 plays an important role during late embryogenesis. Approximately 65% of eggs laid by females that were treated with double-stranded RNA targeting NlVg-like2 failed to hatch, indicating that NlVg-like2 plays a role in nutrition absorption during oocyte, or embryonic development. Our results illustrate the structural and functional differences among the Vg and Vg-like genes and provide potential targets for RNA-interference-based insect pest management strategies.
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Affiliation(s)
- Yan Shen
- State Key Laboratory of Rice Biology, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Science, Zhejiang University, Hangzhou, China
| | - Yuan-Zhi Chen
- State Key Laboratory of Rice Biology, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Science, Zhejiang University, Hangzhou, China
| | - Yi-Han Lou
- State Key Laboratory of Rice Biology, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Science, Zhejiang University, Hangzhou, China
| | - Chuan-Xi Zhang
- State Key Laboratory of Rice Biology, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Science, Zhejiang University, Hangzhou, China
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5
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Abstract
Our understanding of the functions of vitellogenin (Vtg) in reproduction has undergone an evolutionary transformation over the past decade. Primarily, Vtg was regarded as a female-specific reproductive protein, which is cleaved into yolk proteins including phosvitin (Pv) and lipovitellin (Lv), stored in eggs, providing the nutrients for early embryos. Recently, Vtg has been shown to be an immunocomponent factor capable of protecting the host against the attack by microbes including bacteria and viruses. Moreover, Pv and Lv that both are proteolytically cleaved products of maternal Vtg, as well as Pv-derived small peptides, all display an antibacterial role in developing embryos. In addition, both Vtg and yolk protein Pv possess antioxidant activity capable of protecting cells from damage by free radicals. Collectively, these data indicate that Vtg, in addition to being involved in yolk protein formation, also plays non-nutritional roles via functioning as immune-relevant molecules and antioxidant reagents.
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6
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Sun C, Zhang S. Immune-Relevant and Antioxidant Activities of Vitellogenin and Yolk Proteins in Fish. Nutrients 2015. [PMID: 26506386 DOI: 10.3390/nu710543] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2023] Open
Abstract
Vitellogenin (Vtg), the major egg yolk precursor protein, is traditionally thought to provide protein- and lipid-rich nutrients for developing embryos and larvae. However, the roles of Vtg as well as its derived yolk proteins lipovitellin (Lv) and phosvitin (Pv) extend beyond nutritional functions. Accumulating data have demonstrated that Vtg, Lv and Pv participate in host innate immune defense with multifaceted functions. They can all act as multivalent pattern recognition receptors capable of identifying invading microbes. Vtg and Pv can also act as immune effectors capable of killing bacteria and virus. Moreover, Vtg and Lv are shown to possess phagocytosis-promoting activity as opsonins. In addition to these immune-relevant functions, Vtg and Pv are found to have antioxidant activity, which is able to protect the host from oxidant stress. These non-nutritional functions clearly deepen our understanding of the physiological roles of the molecules, and at the same time, provide a sound basis for potential application of the molecules in human health.
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Affiliation(s)
- Chen Sun
- Laboratory for Evolution & Development, Institute of Evolution & Marine Biodiversity and Department of Marine Biology, Ocean University of China, Qingdao 266003, China.
| | - Shicui Zhang
- Laboratory for Evolution & Development, Institute of Evolution & Marine Biodiversity and Department of Marine Biology, Ocean University of China, Qingdao 266003, China.
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7
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Sun C, Zhang S. Immune-Relevant and Antioxidant Activities of Vitellogenin and Yolk Proteins in Fish. Nutrients 2015; 7:8818-29. [PMID: 26506386 PMCID: PMC4632452 DOI: 10.3390/nu7105432] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Revised: 08/24/2015] [Accepted: 08/25/2015] [Indexed: 12/17/2022] Open
Abstract
Vitellogenin (Vtg), the major egg yolk precursor protein, is traditionally thought to provide protein- and lipid-rich nutrients for developing embryos and larvae. However, the roles of Vtg as well as its derived yolk proteins lipovitellin (Lv) and phosvitin (Pv) extend beyond nutritional functions. Accumulating data have demonstrated that Vtg, Lv and Pv participate in host innate immune defense with multifaceted functions. They can all act as multivalent pattern recognition receptors capable of identifying invading microbes. Vtg and Pv can also act as immune effectors capable of killing bacteria and virus. Moreover, Vtg and Lv are shown to possess phagocytosis-promoting activity as opsonins. In addition to these immune-relevant functions, Vtg and Pv are found to have antioxidant activity, which is able to protect the host from oxidant stress. These non-nutritional functions clearly deepen our understanding of the physiological roles of the molecules, and at the same time, provide a sound basis for potential application of the molecules in human health.
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Affiliation(s)
- Chen Sun
- Laboratory for Evolution & Development, Institute of Evolution & Marine Biodiversity and Department of Marine Biology, Ocean University of China, Qingdao 266003, China.
| | - Shicui Zhang
- Laboratory for Evolution & Development, Institute of Evolution & Marine Biodiversity and Department of Marine Biology, Ocean University of China, Qingdao 266003, China.
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8
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Zhang S, Dong Y, Cui P. Vitellogenin is an immunocompetent molecule for mother and offspring in fish. FISH & SHELLFISH IMMUNOLOGY 2015; 46:710-715. [PMID: 26282682 DOI: 10.1016/j.fsi.2015.08.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 08/08/2015] [Accepted: 08/12/2015] [Indexed: 06/04/2023]
Abstract
Our understanding of the function of vitellogenin (Vg) in reproduction has undergone a transformation over the past decade in parallel with new insights into the role of Vg in immunity. Initially, Vg was regarded as a female-specific reproductive protein, which is cleaved into yolk proteins such as phosvitin (Pv) and lipovitellin (Lv), stored in egg, providing the nutrients for developing embryos. Recently, Vg is shown to be an immune-relevant molecule involved in the defense of the host against the microbes including bacterium and virus. Furthermore, Pv and Lv, that both are proteolytically cleaved products of Vg, play a defense role in developing embryos. Importantly, yolk protein-derived small peptides also display antimicrobial activity. These data together indicate that Vg, in addition to being involved in yolk protein formation, plays a non-reproductive role via functioning as an immune-relevant molecule in both parent fishes and their offspring. It also shows that yolk proteins and their degraded peptides are novel players in maternal immunity, opening a new avenue to study the functions of reproductive proteins.
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Affiliation(s)
- Shicui Zhang
- Laboratory for Evolution & Development, Institute of Evolution & Marine Biodiversity and Department of Marine Biology, Ocean University of China, Qingdao 266003, China.
| | - Yuan Dong
- Laboratory for Evolution & Development, Institute of Evolution & Marine Biodiversity and Department of Marine Biology, Ocean University of China, Qingdao 266003, China
| | - Pengfei Cui
- Laboratory for Evolution & Development, Institute of Evolution & Marine Biodiversity and Department of Marine Biology, Ocean University of China, Qingdao 266003, China
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Tobback J, Vuerinckx K, Boerjan B, Huybrechts R. RNA interference mortality points to noncircadian functions for the clock gene in the desert locust Schistocerca gregaria. INSECT MOLECULAR BIOLOGY 2012; 21:369-381. [PMID: 22433062 DOI: 10.1111/j.1365-2583.2012.01143.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
One of the core genes in the circadian regulation network is clock (clk). By forming a heterodimer with CYCLE (CYC) that binds on an E-box in the promoter region, it induces the transcription of other elements in the circadian transcriptional feedback loops and different clock output genes. In contrast to other insects, a clk double-stranded RNA (dsRNA) treatment is lethal in adults and fifth instar nymphs of the desert locust, Schistocerca gregaria, in a dose-dependent manner. Clk knock down fifth instar nymphs are able to undergo their imaginal moult but, depending on the amount of dsRNA, it takes them longer than the controls to reach adulthood. As adults, clk knock down animals do not develop their fat body and ovaries like the control animals. Therefore, we tested the expression of different genes involved in energy metabolism and reproduction to see the effect of the clk RNA interference knock down. Surprisingly, the expression of the vitellogenin gene was up-regulated in the clk knock down females who did not appear to invest their energy in egg development. Taken together, our results point out that the clk gene in the desert locust has an additional function in development besides its established role in maintaining the circadian rhythms in the brain.
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Affiliation(s)
- J Tobback
- Research Group of Insect Physiology and Molecular Ethology, Department of Biology, K.U. Leuven, Leuven, Belgium.
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Alhamdan AA, Alsaif AA. The nutritional, glutathione and oxidant status of elderly subjects admitted to a university hospital. Saudi J Gastroenterol 2011; 17:58-63. [PMID: 21196655 PMCID: PMC3099083 DOI: 10.4103/1319-3767.74474] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Accepted: 04/09/2010] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND/AIM Malnutrition in elderly patients is common in hospitals, and many of the age associated chronic diseases have a common factor, which is oxidative stress. The aim of the study was to evaluate the nutritional status, glutathione, and oxidant status of elderly patients. PATIENTS AND METHODS The mini-nutritional assessment (MNA) was used to determine the nutritional status of elderly patients. Glutathione concentration in the whole blood, plasma albumin, and thiobarbituric acid-reactive substances (TBARS) levels was measured spectrophotometrically by the enzymatic recycling method. In addition, length of hospital stay was estimated. All measurements were taken within 48 h after admission. RESULTS The results showed that more than two-thirds of the elderly were classified as at risk of malnutrition and malnourished. About 45% and 53% elevation in the TBARS was found in at risk of being malnourished and in the malnourished groups, respectively, compared to the well-nourished group, but the elevation did not reach the significant level. No significant differences in the glutathione concentration and in the length of hospital stay were found among the three mini-nutritional assessment categories. CONCLUSIONS The study indicated the necessity of performing the MNA test for elderly upon admission to hospitals, and more attention needs to be paid to this vulnerable group of people.
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Affiliation(s)
- Adel A Alhamdan
- Clinical Nutrition Program, Community Health Sciences Department, College of Applied Medical Sciences, King Saud University, Saudi Arabia.
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11
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The curious case of aging plasticity in honey bees. FEBS Lett 2010; 584:2496-503. [PMID: 20385132 DOI: 10.1016/j.febslet.2010.04.007] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Revised: 03/29/2010] [Accepted: 04/07/2010] [Indexed: 01/01/2023]
Abstract
As in all advanced insect societies, colony-organization in honey bees emerges through a structured division of labor between essentially sterile helpers called workers. Worker bees are sisters that conduct all social tasks except for egg-laying, for example nursing brood and foraging for food. Curiously, aging progresses slowly in workers that engage in nursing and even slower when bees postpone nursing during unfavorable periods. We, therefore, seek to understand how senescence can emerge as a function of social task performance. The alternative utilization of a common yolk precursor protein (vitellogenin) in nursing and somatic maintenance can link behavior and aging plasticity in worker bees. Beneficial effects of vitellogenin may also be mediated by inhibitory action on juvenile hormone and insulin-like signaling.
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12
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Nelson CM, Ihle KE, Fondrk MK, Page RE, Amdam GV. The gene vitellogenin has multiple coordinating effects on social organization. PLoS Biol 2007; 5:e62. [PMID: 17341131 PMCID: PMC1808115 DOI: 10.1371/journal.pbio.0050062] [Citation(s) in RCA: 329] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2006] [Accepted: 01/02/2007] [Indexed: 11/18/2022] Open
Abstract
Temporal division of labor and foraging specialization are key characteristics of honeybee social organization. Worker honeybees (Apis mellifera) initiate foraging for food around their third week of life and often specialize in collecting pollen or nectar before they die. Variation in these fundamental social traits correlates with variation in worker reproductive physiology. However, the genetic and hormonal mechanisms that mediate the control of social organization are not understood and remain a central question in social insect biology. Here we demonstrate that a yolk precursor gene, vitellogenin, affects a complex suite of social traits. Vitellogenin is a major reproductive protein in insects in general and a proposed endocrine factor in honeybees. We show by use of RNA interference (RNAi) that vitellogenin gene activity paces onset of foraging behavior, primes bees for specialized foraging tasks, and influences worker longevity. These findings support the view that the worker specializations that characterize hymenopteran sociality evolved through co-option of reproductive regulatory pathways. Further, they demonstrate for the first time how coordinated control of multiple social life-history traits can originate via the pleiotropic effects of a single gene that affects multiple physiological processes. Animals that live in groups often specialize in different tasks, creating a division of labor. One extreme example can be seen in honeybees, in which most tasks are performed by thousands of worker females that are essentially sterile helpers. Workers start out as nurse bees that care for larvae in the nest. Later they embark on foraging trips, specializing in either pollen or nectar collection, and continue to forage until they die. The age when workers initiate foraging and the tendency to collect pollen or nectar have been linked to a rudimentary reproductive physiology in which the protein vitellogenin appears to play a central role. Vitellogenin is normally used to produce egg yolk, but it may affect behavior and lifespan in workers. We tested this hypothesis by knocking down the vitellogenin gene of worker bees. Workers with suppressed vitellogenin levels foraged earlier, preferred nectar, and lived shorter lives. Thus, vitellogenin has multiple effects on honeybee social organization. By using gene knockdown to understand insect social behavior, our study supports the view that social life in bees evolved by co-opting genes involved in reproduction. vitellogenin gene activity paces onset of foraging behavior in worker bees, demonstrating how coordinated control of multiple social life-history traits can originate via the pleiotropic effects of a single gene.
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Affiliation(s)
- C. Mindy Nelson
- Department of Entomology, University of California Davis, Davis, California, United States of America
| | - Kate E Ihle
- School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
| | - M. Kim Fondrk
- School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
| | - Robert E Page
- School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
| | - Gro V Amdam
- School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
- Department of Animal and Aquacultural Sciences, Norwegian University of Life Sciences, Aas, Norway
- * To whom correspondence should be addressed. E-mail:
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13
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Nakamura A, Yasuda K, Adachi H, Sakurai Y, Ishii N, Goto S. Vitellogenin-6 is a major carbonylated protein in aged nematode, Caenorhabditis elegans. Biochem Biophys Res Commun 1999; 264:580-3. [PMID: 10529405 DOI: 10.1006/bbrc.1999.1549] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recently we found that protein carbonyl content increases with age in wild-type as well as long- and short-lived Caenorhabditis elegans nematodes in inverse correlation with life span (Adachi et al., J. Gerontol. 53A, B240-B244, 1998; Yasuda et al., J. Gerontol. 54A, B47-B51, 1999). In the present study, we investigated carbonyl modification of individual proteins in young and old wild-type nematodes by two-dimensional immunoblot using antibodies against 2, 4-dinitrophenylhydrazones. A protein with apparent molecular weight of 110 kDa was found to be a major carbonylated protein in aged animals. Amino acid sequence of peptide fragments of the protein was identical to that of vitellogenin-6, a yolk protein synthesized in and secreted from the intestine during egg-laying stage. Although the function(s) of the protein in aged nematodes is unclear, we suggest that the protein may have a role to protect other cellular components from oxidation because of its metal binding capacity.
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Affiliation(s)
- A Nakamura
- Department of Biochemistry, School of Pharmaceutical Sciences, Toho University, Japan
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