1
|
Zhang B, Chai Y, Xu Y, Huang Z, Hu X, Li Y. Impact Analysis of Photoperiodic Disorder on the Eyestalk of Chinese Mitten Crab ( Eriocheir sinensis) through High-Throughput Sequencing Technology. Life (Basel) 2024; 14:209. [PMID: 38398718 PMCID: PMC10890049 DOI: 10.3390/life14020209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 01/20/2024] [Accepted: 01/30/2024] [Indexed: 02/25/2024] Open
Abstract
Light is an indispensable factor in the healthy growth of living organisms, and alterations in the photoperiod can have consequences for body homeostasis. The eyestalk is a photosensitive organ that secretes various hormones to regulate the Chinese mitten crab (Eriocheir sinensis). However, the photoperiod-dependent eyestalk patterns of gene expression that may underlie changes in body homeostasis are unknown. In this study, we investigated the molecular mechanisms involved in eyestalk transcriptomic responses in E. sinensis under different photoperiod regimes on days 2, 4, and 6. The photoperiods tested were 12, 24, and 0 h light/day. In total, we obtained 110, 958, 348 clean datasets and detected 1809 differentially expressed genes (DEGs). Genes involved in the crustacean hyperglycemic hormone superfamily and juvenile hormones were observed, which play important roles in gonadal development, growth, and immunity in E. sinensis and may also be involved in photoperiod adaptation. In addition, the MAPK signaling pathway was the only signaling pathway identified in the continuous light group but was absent in the continuous darkness group. We suggest that the MAPK pathway is highly responsive to light input during the subjective night and insensitive to light during the middle of the subjective day. These results provide insight into the molecular mechanisms underlying the effects of photoperiod on the immune regulation of E. sinensis.
Collapse
Affiliation(s)
| | | | | | | | | | - Yingdong Li
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang 110866, China
| |
Collapse
|
2
|
Yu C, Zhang B, Zhang Z, Wang S, Wei T, Li L, Zhao Y, Wei H, Li Y. Comparative transcriptome analysis reveals the impact of the daily rhythm on the hemolymph of the Chinese mitten crab ( Eriocheir sinensis). Chronobiol Int 2022; 39:805-817. [PMID: 35144513 DOI: 10.1080/07420528.2022.2035744] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The daily rhythm affects a series of physiological functions in crustaceans. To study its effect on the physiological function in Eriocheir sinensis, a crustacean species of high economic value, we analyzed the hemolymph transcriptome during the daily rhythm by high-throughput sequencing. We sampled the hemolymph from crabs at four time points in a single day (06:00, 12:00, 18:00, and 24:00 h) and identified 3,01,661 and 1,03,998 transcripts and unigenes, respectively; some of the unigenes were annotated as core clock genes. Moreover, 15,564 differentially expressed genes (DEGs) were divided into nine different clusters. Functional enrichment analysis of DEGs indicated that the molting, metabolism, and immunity processes in E. sinensis were impacted by its daily rhythm. In addition, we mapped the DEGs involved in the daily entrainment pathway. To the best of our knowledge, this is the first comparative transcriptome analysis of crustacean hemolymph during the day-night cycle, and provides multi-level information for unraveling the finer regulatory effects of the daily cycle in crustaceans.
Collapse
Affiliation(s)
- Changyue Yu
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Baoli Zhang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Zhiyuan Zhang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Simiao Wang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Tingyu Wei
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Lisong Li
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Yingying Zhao
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Hua Wei
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Yingdong Li
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| |
Collapse
|
3
|
Oyarzabal-Armendariz E, Alquicira-Mireles J, Zúñiga-Ruíz B, Arreola-Ramírez JL, Guevara-Fefer P, Lara-Figueroa CO, Escamilla-Chimal EG. Effect of Azadirachta indica A. Juss (Meliaceae) on the serotonin rhythm of Spodoptera frugiperda (Lepidoptera: Noctuidae). Chronobiol Int 2021; 38:201-211. [PMID: 33397171 DOI: 10.1080/07420528.2020.1858849] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Circadian rhythms are an adaptive response of organisms to the environment that enables them to measure time. Circadian rhythms are some of the most studied biological rhythms. Serotonin (5HT) has been proposed as their modulator of circadian rhythms, playing a pivotal role in their establishment. However, 5HT concentrations are altered in insect organisms when they feed on some plant extracts. Insects show a variety of rhythms. The larval stage of the lepidopteran Spodoptera frugiperda is a pest of economically important crops. As a response, plants have developed secondary metabolites, such as azadirachtin, obtained from Azadirachta indica. We assessed the circadian rhythm of 5HT in the brain and digestive tube of larvae of S. frugiperda; furthermore, the effect of A. indica extract on the oscillations was evaluated. 5HT modulates the rhythms of locomotor activity, and if extracts of A. indica alter the concentration of 5HT, it can indirectly alter the rhythms of locomotor activity, as well as peristaltic movements of the intestine. Larvae were exposed to a 12 h:12 h light-dark (LD) photoperiod, and half of them remained for 72 h under constant darkness (DD). Tissue samples were obtained at six different times during a single 24 h period, and the amount of 5HT was quantified by high-performance liquid chromatography (HPLC). Data were statistically compared by a one-way ANOVA followed by a Tukey post hoc test and subjected to Cosinor analysis for assessment of 24 h rhythmicity. The results showed that the A. indica methanolic extract had an effect on the 5HT concentration of the brain and digestive tube of the larvae. In the brain, the 5HT increase in larvae fed with the extract could alter memory, learning, sleep, and locomotor activity processes. Whereas in the intestine, the 5HT decrease in the larvae fed with the extract could decrease peristalsis movements and, therefore, indirectly influence the antifeedant effect.
Collapse
Affiliation(s)
- Erick Oyarzabal-Armendariz
- Departamento de Ecología y Recursos Naturales, Facultad de Ciencias, Universidad Nacional Autónoma de México , Mexico City, Mexico
| | - Jesús Alquicira-Mireles
- Departamento de Hiperreactividad Bronquial, Instituto Nacional de Enfermedades Respiratorias Ismael Cosio Villegas , Mexico City, Mexico
| | - Beatriz Zúñiga-Ruíz
- Departamento de Ecología y Recursos Naturales, Facultad de Ciencias, Universidad Nacional Autónoma de México , Mexico City, Mexico
| | - José Luis Arreola-Ramírez
- Departamento de Hiperreactividad Bronquial, Instituto Nacional de Enfermedades Respiratorias Ismael Cosio Villegas , Mexico City, Mexico
| | - Patricia Guevara-Fefer
- Departamento de Ecología y Recursos Naturales, Facultad de Ciencias, Universidad Nacional Autónoma de México , Mexico City, Mexico
| | - César Oliver Lara-Figueroa
- Laboratorio Nacional de Canalopatías, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México , Mexico City, Mexico
| | - Elsa G Escamilla-Chimal
- Departamento de Ecología y Recursos Naturales, Facultad de Ciencias, Universidad Nacional Autónoma de México , Mexico City, Mexico
| |
Collapse
|
4
|
Chen HY, Toullec JY, Lee CY. The Crustacean Hyperglycemic Hormone Superfamily: Progress Made in the Past Decade. Front Endocrinol (Lausanne) 2020; 11:578958. [PMID: 33117290 PMCID: PMC7560641 DOI: 10.3389/fendo.2020.578958] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 09/09/2020] [Indexed: 12/11/2022] Open
Abstract
Early studies recognizing the importance of the decapod eyestalk in the endocrine regulation of crustacean physiology-molting, metabolism, reproduction, osmotic balance, etc.-helped found the field of crustacean endocrinology. Characterization of putative factors in the eyestalk using distinct functional bioassays ultimately led to the discovery of a group of structurally related and functionally diverse neuropeptides, crustacean hyperglycemic hormone (CHH), molt-inhibiting hormone (MIH), gonad-inhibiting hormone (GIH) or vitellogenesis-inhibiting hormone (VIH), and mandibular organ-inhibiting hormone (MOIH). These peptides, along with the first insect member (ion transport peptide, ITP), constitute the original arthropod members of the crustacean hyperglycemic hormone (CHH) superfamily. The presence of genes encoding the CHH-superfamily peptides across representative ecdysozoan taxa has been established. The objective of this review is to, aside from providing a general framework, highlight the progress made during the past decade or so. The progress includes the widespread identification of the CHH-superfamily peptides, in particular in non-crustaceans, which has reshaped the phylogenetic profile of the superfamily. Novel functions have been attributed to some of the newly identified members, providing exceptional opportunities for understanding the structure-function relationships of these peptides. Functional studies are challenging, especially for the peptides of crustacean and insect species, where they are widely expressed in various tissues and usually pleiotropic. Progress has been made in deciphering the roles of CHH, ITP, and their alternatively spliced counterparts (CHH-L, ITP-L) in the regulation of metabolism and ionic/osmotic hemostasis under (eco)physiological, developmental, or pathological contexts, and of MIH in the stimulation of ovarian maturation, which implicates it as a regulator for coordinating growth (molt) and reproduction. In addition, experimental elucidation of the steric structure and structure-function relationships have given better understanding of the structural basis of the functional diversification and overlapping among these peptides. Finally, an important finding was the first-ever identification of the receptors for this superfamily of peptides, specifically the receptors for ITPs of the silkworm, which will surely give great impetus to the functional study of these peptides for years to come. Studies regarding recent progress are presented and synthesized, and prospective developments remarked upon.
Collapse
Affiliation(s)
- Hsiang-Yin Chen
- Department of Aquaculture, National Penghu University of Science and Technology, Magong, Taiwan
| | - Jean-Yves Toullec
- Sorbonne Université, Faculté des Sciences, CNRS, UMR 7144, Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, Roscoff, France
| | - Chi-Ying Lee
- Graduate Program of Biotechnology and Department of Biology, National Changhua University of Education, Changhua, Taiwan
| |
Collapse
|
5
|
Crustacean hyperglycemic hormone is synthesized in the eyestalk and brain of the crayfish Procambarus clarkii. PLoS One 2017; 12:e0175046. [PMID: 28369112 PMCID: PMC5378376 DOI: 10.1371/journal.pone.0175046] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 03/20/2017] [Indexed: 12/11/2022] Open
Abstract
Crustacean hyperglycemic hormone (CHH) is a neuropeptide that is synthesized, stored, and released by brain and eyestalk structures in decapods. CHH participates in the regulation of several mechanisms, including increasing the level of glucose in hemolymph. Although CHH mRNA levels have been quantified and the CHH protein has been localized in various structures of the crayfish P. clarkii, CHH synthesis has only been reported in the X-organ-sinus gland (XO-SG). Therefore, the aim of this study was to use in situ hybridization to determine whether CHH mRNA is located in other structures, including the putative pacemaker, eyestalk and brain, of crayfish P. clarkii at two times of day. CHH mRNA was observed in both the eyestalk and the brain of P. clarkii, indicating that CHH is synthesized in several structures in common with other crustaceans, possibly to provide metabolic support for these regions by increasing glucose levels.
Collapse
|
6
|
Chen S, Qiao H, Fu H, Sun S, Zhang W, Jin S, Gong Y, Jiang S, Xiong W, YanWu. Molecular cloning, characterization, and temporal expression of the clock genes period and timeless in the oriental river prawn Macrobrachium nipponense during female reproductive development. Comp Biochem Physiol A Mol Integr Physiol 2017; 207:43-51. [PMID: 28192242 DOI: 10.1016/j.cbpa.2017.02.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Revised: 02/08/2017] [Accepted: 02/08/2017] [Indexed: 10/20/2022]
Abstract
The circadian clock is crucial for sustaining rhythmic biochemical, physiological, and behavioral processes in living creatures. In this study, we isolated and characterized two circadian clock genes in Macrobrachium nipponense, period (Mnper) and timeless (Mntim). The complete Mnper cDNA measures 4283bp in length with an open reading frame encoding 1292 amino acids, including functional domains such as PER-ARNT-SIM (PAS), cytoplasmic localization domain (CLD), TIM interaction site (TIS), and nuclear localization signal (NLS). The deduced Mntim protein comprises1540 amino acids with functional domains such as PER interaction site (PIS), NLS, and CLD. Tissue distribution analyses showed that the two genes were highly expressed in the eyestalk and brain in both males and females, as well as being expressed in the ovary. The expression profiles of Mnper and Mntim were determined in the eyestalk, brain, and ovary under simulated breeding season and non-breeding season conditions. The expression profiles of both Mnper and Mntim appeared to be unaffected in the eyestalk. However, the expression of both genes exhibited significant seasonal variations in the brain, and thus we assumed the brain to be their functional location. The expression profiles under different simulated seasons and the variations during different ovarian stages indicate that both genes might be involved with female reproduction. Especially the mRNA levels in the brain varied greatly during these stages indicating that the clock function in the brain is closely related to ovarian development and female reproduction. And the reproductive roles of clock genes need to be elucidated.
Collapse
Affiliation(s)
- SuHua Chen
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, PR China
| | - Hui Qiao
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, PR China
| | - HongTuo Fu
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, PR China; Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, PR China.
| | - Shengming Sun
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, PR China
| | - WenYi Zhang
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, PR China
| | - ShuBo Jin
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, PR China
| | - Yongsheng Gong
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, PR China
| | - Sufei Jiang
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, PR China
| | - Weiyi Xiong
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, PR China
| | - YanWu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, PR China
| |
Collapse
|
7
|
Rodríguez-Muñoz MDLP, Escamilla-Chimal EG. Glial fibrillary acidic protein (GFAP) shows circadian oscillations in crayfishProcambarus clarkiiputative pacemakers. Chronobiol Int 2015; 32:1135-44. [DOI: 10.3109/07420528.2015.1071385] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
8
|
Nelson-Mora J, Prieto-Sagredo J, Loredo-Ranjel R, Fanjul-Moles ML. Putative pacemakers in the eyestalk and brain of the crayfish Procambarus clarkii show circadian oscillations in levels of mRNA for crustacean hyperglycemic hormone. PLoS One 2013; 8:e83937. [PMID: 24391849 PMCID: PMC3877119 DOI: 10.1371/journal.pone.0083937] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Accepted: 11/19/2013] [Indexed: 11/21/2022] Open
Abstract
Crustacean hyperglycemic hormone (CHH) synthesizing cells in the optic lobe, one of the pacemakers of the circadian system, have been shown to be present in crayfish. However, the presence of CHH in the central brain, another putative pacemaker of the multi-oscillatory circadian system, of this decapod and its circadian transcription in the optic lobe and brain have yet to be explored. Therefore, using qualitative and quantitative PCR, we isolated and cloned a CHH mRNA fragment from two putative pacemakers of the multi-oscillatory circadian system of Procambarus clarkii, the optic lobe and the central brain. This CHH transcript synchronized to daily light-dark cycles and oscillated under dark, constant conditions demonstrating statistically significant daily and circadian rhythms in both structures. Furthermore, to investigate the presence of the peptide in the central brain of this decapod, we used immunohistochemical methods. Confocal microscopy revealed the presence of CHH-IR in fibers and cells of the protocerebral and tritocerebal clusters and neuropiles, particularly in some neurons located in clusters 6, 14, 15 and 17. The presence of CHH positive neurons in structures of P. clarkii where clock proteins have been reported suggests a relationship between the circadian clockwork and CHH. This work provides new insights into the circadian regulation of CHH, a pleiotropic hormone that regulates many physiological processes such as glucose metabolism and osmoregulatory responses to stress.
Collapse
Affiliation(s)
- Janikua Nelson-Mora
- Laboratorio de Neurofisiología Comparada, Departamento de Ecología y Recursos Naturales, Facultad de Ciencias, Universidad Nacional Autónoma de México, Distrito Federal, México
| | - Julio Prieto-Sagredo
- Laboratorio de Neurofisiología Comparada, Departamento de Ecología y Recursos Naturales, Facultad de Ciencias, Universidad Nacional Autónoma de México, Distrito Federal, México
| | - Rosaura Loredo-Ranjel
- Laboratorio de Neurofisiología Comparada, Departamento de Ecología y Recursos Naturales, Facultad de Ciencias, Universidad Nacional Autónoma de México, Distrito Federal, México
| | - María Luisa Fanjul-Moles
- Laboratorio de Neurofisiología Comparada, Departamento de Ecología y Recursos Naturales, Facultad de Ciencias, Universidad Nacional Autónoma de México, Distrito Federal, México
| |
Collapse
|
9
|
The Antarctic krill Euphausia superba shows diurnal cycles of transcription under natural conditions. PLoS One 2013; 8:e68652. [PMID: 23874706 PMCID: PMC3714250 DOI: 10.1371/journal.pone.0068652] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 05/30/2013] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Polar environments are characterized by extreme seasonal changes in day length, light intensity and spectrum, the extent of sea ice during the winter, and food availability. A key species of the Southern Ocean ecosystem, the Antarctic krill (Euphausia superba) has evolved rhythmic physiological and behavioral mechanisms to adapt to daily and seasonal changes. The molecular organization of the clockwork underlying these biological rhythms is, nevertheless, still only partially understood. METHODOLOGY/PRINCIPAL FINDINGS The genome sequence of the Antarctic krill is not yet available. A normalized cDNA library was produced and pyrosequenced in the attempt to identify large numbers of transcripts. All available E. superba sequences were then assembled to create the most complete existing oligonucleotide microarray platform with a total of 32,217 probes. Gene expression signatures of specimens collected in the Ross Sea at five different time points over a 24-hour cycle were defined, and 1,308 genes differentially expressed were identified. Of the corresponding transcripts, 609 showed a significant sinusoidal expression pattern; about 40% of these exibithed a 24-hour periodicity while the other 60% was characterized by a shorter (about 12-hour) rhythm. We assigned the differentially expressed genes to functional categories and noticed that those concerning translation, proteolysis, energy and metabolic process, redox regulation, visual transduction and stress response, which are most likely related to daily environmental changes, were significantly enriched. Two transcripts of peroxiredoxin, thought to represent the ancestral timekeeping system that evolved about 2.5 billion years ago, were also identified as were two isoforms of the EsRh1 opsin and two novel arrestin1 sequences involved in the visual transduction cascade. CONCLUSIONS Our work represents the first characterization of the krill diurnal transcriptome under natural conditions and provides a first insight into the genetic regulation of physiological changes, which occur around the clock during an Antarctic summer day.
Collapse
|
10
|
Velázque-Amado RM, Escamilla-Chimal EG, Fanjul-Moles ML. Daily Light-Dark Cycles Influence Hypoxia-Inducible Factor 1 and Heat Shock Protein Levels in the Pacemakers of Crayfish. Photochem Photobiol 2011; 88:81-9. [DOI: 10.1111/j.1751-1097.2011.01012.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
|
11
|
A circadian clock in Antarctic krill: an endogenous timing system governs metabolic output rhythms in the euphausid species Euphausia superba. PLoS One 2011; 6:e26090. [PMID: 22022521 PMCID: PMC3189233 DOI: 10.1371/journal.pone.0026090] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Accepted: 09/19/2011] [Indexed: 02/05/2023] Open
Abstract
Antarctic krill, Euphausia superba, shapes the structure of the Southern Ocean ecosystem. Its central position in the food web, the ongoing environmental changes due to climatic warming, and increasing commercial interest on this species emphasize the urgency of understanding the adaptability of krill to its environment. Krill has evolved rhythmic physiological and behavioral functions which are synchronized with the daily and seasonal cycles of the complex Southern Ocean ecosystem. The mechanisms, however, leading to these rhythms are essentially unknown. Here, we show that krill possesses an endogenous circadian clock that governs metabolic and physiological output rhythms. We found that expression of the canonical clock gene cry2 was highly rhythmic both in a light-dark cycle and in constant darkness. We detected a remarkable short circadian period, which we interpret as a special feature of the krill's circadian clock that helps to entrain the circadian system to the extreme range of photoperiods krill is exposed to throughout the year. Furthermore, we found that important key metabolic enzymes of krill showed bimodal circadian oscillations (∼9–12 h period) in transcript abundance and enzymatic activity. Oxygen consumption of krill showed ∼9–12 h oscillations that correlated with the temporal activity profile of key enzymes of aerobic energy metabolism. Our results demonstrate the first report of an endogenous circadian timing system in Antarctic krill and its likely link to metabolic key processes. Krill's circadian clock may not only be critical for synchronization to the solar day but also for the control of seasonal events. This study provides a powerful basis for the investigation into the mechanisms of temporal synchronization in this marine key species and will also lead to the first comprehensive analyses of the circadian clock of a polar marine organism through the entire photoperiodic cycle.
Collapse
|
12
|
Strauß J, Zhang Q, Verleyen P, Huybrechts J, Neupert S, Predel R, Pauwels K, Dircksen H. Pigment-dispersing hormone in Daphnia interneurons, one type homologous to insect clock neurons displaying circadian rhythmicity. Cell Mol Life Sci 2011; 68:3403-23. [PMID: 21365282 PMCID: PMC11115014 DOI: 10.1007/s00018-011-0636-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Revised: 01/29/2011] [Accepted: 02/01/2011] [Indexed: 10/18/2022]
Abstract
We report identification of a beta-type pigment-dispersing hormone (PDH) identical in two water flea species, Daphnia magna and Daphnia pulex. It has been identified by cloning of precursors, chromatographic isolation from tissue extracts followed by immunoassays and de novo-mass spectrometric sequencing. The peptide is restricted to a complex system of distinct interneurons in the brain and visual ganglia, but does not occur in neurosecretory cells projecting to neurohemal organs as in decapod crustaceans. Thirteen neuron types individually identified and reconstructed by immunohistochemistry were almost identical in terms of positions and projection patterns in both species. Several neurons invade and form plexuses in visual ganglia and major brain neuropils including the central body. Five neuron types show contralateral pathways and form plexuses in the lateral, dorsal, or postlateral brain neuropils. Others are local interneurons, and a tritocerebral neuron connects the protocerebrum with the neuropil of the locomotory second antenna. Two visual ganglia neuron types lateral to the medulla closely resemble insect medulla lateral circadian clock neurons containing pigment-dispersing factor based upon positional and projectional criteria. Experiments under 12:12 h light/dark cycles and constant light or darkness conditions showed significant circadian changes in numbers and activities of one type of medulla lateral PDH neuron with an acrophase in the evening. This simple PDH system shows striking homologies to PDH systems in decapod crustaceans and well-known clock neurons in several insects, which suggests evolutionary conservation of an ancient peptidergic interneuronal system that is part of biological clocks.
Collapse
Affiliation(s)
- Johannes Strauß
- Department of Zoology, Stockholm University, Svante Arrhenius väg 18A, 10691 Stockholm, Sweden
| | - Qian Zhang
- Dr. Senckenbergische Anatomie, Institute of Anatomy II, J.-W. Goethe-University of Frankfurt, Frankfurt, Germany
| | | | | | - Susanne Neupert
- Institute of General Zoology and Animal Physiology, Friedrich-Schiller-University, Jena, Germany
| | - Reinhard Predel
- Institute of General Zoology and Animal Physiology, Friedrich-Schiller-University, Jena, Germany
| | - Kevin Pauwels
- Department of Biology, K. U. Leuven, Leuven, Belgium
| | - Heinrich Dircksen
- Department of Zoology, Stockholm University, Svante Arrhenius väg 18A, 10691 Stockholm, Sweden
| |
Collapse
|