1
|
Takeda M, Suzuki T. Circadian and Neuroendocrine Basis of Photoperiodism Controlling Diapause in Insects and Mites: A Review. Front Physiol 2022; 13:867621. [PMID: 35812309 PMCID: PMC9257128 DOI: 10.3389/fphys.2022.867621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 05/02/2022] [Indexed: 11/13/2022] Open
Abstract
The photoperiodic system is concealed in the highly complex black-box, comprising four functional subunits: 1) a photo/thermo-sensitive input unit, 2) a photoperiodic clock based on a circadian system, 3) a condenser unit counting the number of inductive signals, and 4) a neuroendocrine switch that triggers a phenotypic shift. This review aims to summarize the research history and current reach of our understanding on this subject to connect it with the molecular mechanism of the circadian clock rapidly being unveiled. The review also focuses on the mode of intersubunit information transduction. It will scan the recent advancement in research on each functional subunit, but special attention will be given to the circadian clock-endocrine conjunct and the role of melatonin signaling in the regulation of insect photoperiodism. Prothoracicotropic hormone (PTTH) probably plays the most crucial role in the regulation of pupal diapause, which is the simplest model system of diapause regulation by hormones investigated so far, particularly in the Chinese oak silkmoth (Antheraea pernyi). A search for the trigger to release the PTTH found some candidates, that is, indoleamines. Indolamine metabolism is controlled by arylalkylamine N-acetyltransferase (aaNAT). Indolamine dynamics and aaNAT enzymatic activity changed according to photoperiods. aaNAT activity and melatonin content in the brain showed not only a photoperiodic response but also a circadian fluctuation. aaNAT had multiple E-boxes, suggesting that it is a clock-controlled gene (ccg), which implies that cycle (cyc, or brain-muscle Arnt-like 1 = Bmal1)/Clock (Clk) heterodimer binds to E-box and stimulates the transcription of aaNAT, which causes the synthesis of melatonin. RNAi against transcription modulators, cyc, or Clk downregulated aaNAT transcription, while RNAi against repressor of cyc/Clk, per upregulated aaNAT transcription. Immunohistochemical localization showed that the circadian neurons carry epitopes of melatonin-producing elements such as aaNAT, the precursor serotonin, HIOMT, and melatonin as well as clock gene products such as cyc-ir, Per-ir, and dbt-ir, while PTTH-producing neurons juxtaposed against the clock neurons showed hMT2-ir in A. pernyi brain. Melatonin probably binds to the putative melatonin receptor (MT) that stimulates Ca2+ influx, which in turn activates PKC. This induces Rab 8 phosphorylation and exocytosis of PTTH, leading to termination of diapause. All the PTTH-expressing neurons have PKC-ir, and Rab8-ir. When diapause is induced and maintained under short days, serotonin binding to 5HTR1B suppresses PTTH release in a yet unknown way. RNAi against this receptor knocked out photoperiodism; short day response is blocked and diapause was terminated even under the short day condition. The result showed that a relatively simple system controls both induction and termination in pupal diapause of A. pernyi: the circadian system regulates the transcription of aaNAT as a binary switch, the enzyme produces a melatonin rhythm that gates PTTH release, and 5HTR1B and MT are probably also under photoperiodic regulation. Finally, we listed the remaining riddles which need to be resolved, to fully understand this highly complex system in future studies.
Collapse
Affiliation(s)
- Makio Takeda
- Graduate School of Agricultural Science, Kobe University, Kobe, Japan
| | - Takeshi Suzuki
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan
| |
Collapse
|
2
|
O'Flynn BG, Suarez G, Hawley AJ, Merkler DJ. Insect Arylalkylamine N-Acyltransferases: Mechanism and Role in Fatty Acid Amide Biosynthesis. Front Mol Biosci 2018; 5:66. [PMID: 30094237 PMCID: PMC6070697 DOI: 10.3389/fmolb.2018.00066] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 06/26/2018] [Indexed: 01/29/2023] Open
Abstract
Arylalkylamine N-acyltransferases (AANATs) catalyze the formation of an N-acylamide from an acyl-CoA thioester and an amine. One well known example is the production of N-acetylserotonin from acetyl-CoA and serotonin, a reaction in the melatonin biosynthetic pathway from tryptophan. AANATs have been identified from a variety of vertebrates and invertebrates. Considerable efforts have been devoted to the mammalian AANAT because a cell-permeable inhibitor specifically targeted against this enzyme could prove useful to treat diseases related to dysfunction in melatonin production. Insects are an interesting model for the study of AANATs because more than one isoform is typically expressed by a specific insect and the different insect AANATs (iAANATs) serve different roles in the insect cell. In contrast, mammals express only one AANAT. The major role of iAANATs seem to be in the production of N-acetyldopamine, a reaction important in the tanning and sclerotization of the cuticle. Metabolites identified in insects including N-acetylserotonin and long-chain N-fatty acyl derivatives of dopamine, histidine, phenylalanine, serotonin, tyrosine, and tryptophan are likely produced by an iAANAT. In vitro studies of specific iAANATs are consistent with this hypothesis. In this review, we highlight the current metabolomic knowledge of the N-acylated aromatic amino acids and N-acylated derivatives of the aromatic amino acids, the current mechanistic understanding of the iAANATs, and explore the possibility that iAANATs serve as insect "rhymezymes" regulating photoperiodism and other rhythmic processes in insects.
Collapse
Affiliation(s)
| | | | | | - David J. Merkler
- Department of Chemistry, University of South Florida, Tampa, FL, United States
| |
Collapse
|
3
|
Guan H, Wang M, Liao C, Liang J, Mehere P, Tian M, Liu H, Robinson H, Li J, Han Q. Identification of aaNAT5b as a spermine N-acetyltransferase in the mosquito, Aedes aegypti. PLoS One 2018; 13:e0194499. [PMID: 29554129 PMCID: PMC5858766 DOI: 10.1371/journal.pone.0194499] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2017] [Accepted: 03/05/2018] [Indexed: 11/21/2022] Open
Abstract
Mosquitoes transmit a number of diseases in animals and humans, including Dengue, Chikungunya and Zika viruses that affect millions of people each year. Controlling the disease-transmitting mosquitoes has proven to be a successful strategy to reduce the viruses transmission. Polyamines are required for the life cycle of the RNA viruses, Chikungunya virus and Zika virus, and a depletion of spermidine and spermine in the host via induction of spermine N-acetyltransferase restricts their replication. Spermine N-acetyltransferase is a key catabolic enzyme in the polyamine pathway, however there is no information of the enzyme identification in any insects. Aliphatic polyamines play a fundamental role in tissue growth and development in organisms. They are acetylated by spermidine/spermine N1-acetyltransferase (SAT). In this study we provided a molecular and biochemical identification of SAT from Aedes aegypti mosquitoes. Screening of purified recombinant proteins against polyamines established that aaNAT5b, named previously based on sequence similarity with identified aaNAT1 in insects, is active to spermine and spermidine. A crystal structure was determined and used in molecular docking in this study. Key residues were identified to be involved in spermine binding using molecular docking and simulation. In addition, SAT transcript was down regulated by blood feeding using a real time PCR test. Based on its substrate profile and transcriptional levels after blood feeding, together with previous reports for polyamines required in arboviruses replication, SAT might be potentially used as a target to control arboviruses with human interference.
Collapse
Affiliation(s)
- Huai Guan
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Hainan University, Haikou, Hainan, China
- Laboratory of Tropical Veterinary Medicine and Vector Biology, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan, China
| | - Maoying Wang
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Hainan University, Haikou, Hainan, China
- Laboratory of Tropical Veterinary Medicine and Vector Biology, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan, China
| | - Chenghong Liao
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Hainan University, Haikou, Hainan, China
- Laboratory of Tropical Veterinary Medicine and Vector Biology, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan, China
| | - Jing Liang
- Krantisinh Nana Patil College of Veterinary Science, Shirval, India
| | - Prajwalini Mehere
- Department of Biochemistry, Virginia Tech, Blacksburg, Virginia, United States of America
| | - Meiling Tian
- Laboratory of Tropical Veterinary Medicine and Vector Biology, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan, China
| | - Hairong Liu
- Laboratory of Tropical Veterinary Medicine and Vector Biology, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan, China
| | - Howard Robinson
- Biology Department, Brookhaven National Laboratory, Upton, New York, United States of America
| | - Jianyong Li
- Krantisinh Nana Patil College of Veterinary Science, Shirval, India
| | - Qian Han
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Hainan University, Haikou, Hainan, China
- Laboratory of Tropical Veterinary Medicine and Vector Biology, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan, China
- * E-mail: ,
| |
Collapse
|
4
|
Noh MY, Koo B, Kramer KJ, Muthukrishnan S, Arakane Y. Arylalkylamine N-acetyltransferase 1 gene (TcAANAT1) is required for cuticle morphology and pigmentation of the adult red flour beetle, Tribolium castaneum. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2016; 79:119-129. [PMID: 27816487 DOI: 10.1016/j.ibmb.2016.10.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 10/27/2016] [Accepted: 10/31/2016] [Indexed: 06/06/2023]
Abstract
In the insect cuticle tanning pathway (sclerotization and pigmentation), the enzyme arylalkylamine N-acetyltransferase (AANAT) catalyzes the acetylation of dopamine to form N-acetyldopamine (NADA), which is one of the major precursors for quinone-mediated tanning. In this study we characterized and investigated the function of TcAANAT1 in cuticle pigmentation of the red flour beetle, Tribolium castaneum. We isolated a full length TcAANAT1 cDNA that encodes a protein of 256 amino acid residues with a predicted GCN5-related acetyltransferase domain containing an acetyl-CoA binding motif. TcAANAT1 transcripts were detected at all stages of development with lowest expressions at the embryonic and pharate pupal stages. We expressed and purified the encoded recombinant TcAANAT1 protein (rTcAANAT1) that exhibited highest activity at slightly basic pH values (for example, pH 7.5 to 8.5 using dopamine as the substrate). In addition, rTcAANAT1 acts on a wide range of substrates including tryptamine, octopamine and norepinephrine with similar substrate affinities with Km values in the range of 0.05-0.11 mM except for tyramine (Km = 0.56 mM). Loss of function of TcAANAT1 caused by RNAi had no effect on larval and pupal development. The tanning of pupal setae, gin traps and urogomphi proceeded normally. However, the resulting adults (∼70%) exhibited a roughened exoskeletal surface, separated elytra and improperly folded hindwings. The body wall, elytra and veins of the hindwing of the mature adults were significantly darker than those of control insects probably due to the accumulation of dopamine melanin. A dark pigmentation surrounding the bristles located on the inter-veins of the elytron was evident primarily because of the underlying darkly pigmented trabeculae that partition the dorsal and ventral layers of the elytron. These results support the hypothesis that TcAANAT1 acetylates dopamine and plays a role in development of the morphology and pigmentation of T. castaneum adult cuticle.
Collapse
Affiliation(s)
- Mi Young Noh
- Department of Applied Biology, Chonnam National University, Gwangju 500-757, South Korea
| | - Bonwoo Koo
- Department of Applied Biology, Chonnam National University, Gwangju 500-757, South Korea
| | - Karl J Kramer
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS 66506, USA
| | - Subbaratnam Muthukrishnan
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS 66506, USA
| | - Yasuyuki Arakane
- Department of Applied Biology, Chonnam National University, Gwangju 500-757, South Korea.
| |
Collapse
|
5
|
A Pathway Analysis of Melanin Patterning in a Hemimetabolous Insect. Genetics 2016; 203:403-13. [PMID: 26984060 DOI: 10.1534/genetics.115.186684] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 03/02/2016] [Indexed: 11/18/2022] Open
Abstract
Diversity in insect pigmentation, encompassing a wide range of colors and spatial patterns, is among the most noticeable features distinguishing species, individuals, and body regions within individuals. In holometabolous species, a significant portion of such diversity can be attributed to the melanin synthesis genes, but this has not been formally assessed in more basal insect lineages. Here we provide a comprehensive analysis of how a set of melanin genes (ebony, black, aaNAT, yellow, and tan) contributes to the pigmentation pattern in a hemipteran, Oncopeltus fasciatus For all five genes, RNA interference depletion caused alteration of black patterning in a region-specific fashion. Furthermore, the presence of distinct nonblack regions in forewings and hindwings coincides with the expression of ebony and aaNAT in these appendages. These findings suggest that the region-specific phenotypes arise from regional employment of various combinations of the melanin genes. Based on this insight, we suggest that melanin genes are used in two distinct ways: a "painting" mode, using predominantly melanin-promoting factors in areas that generally lack black coloration, and, alternatively, an "erasing" mode, using mainly melanin-suppressing factors in regions where black is the dominant pigment. Different combinations of these strategies may account for the vast diversity of melanin patterns observed in insects.
Collapse
|
6
|
Hiragaki S, Suzuki T, Mohamed AAM, Takeda M. Structures and functions of insect arylalkylamine N-acetyltransferase (iaaNAT); a key enzyme for physiological and behavioral switch in arthropods. Front Physiol 2015; 6:113. [PMID: 25918505 PMCID: PMC4394704 DOI: 10.3389/fphys.2015.00113] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 03/25/2015] [Indexed: 11/26/2022] Open
Abstract
The evolution of N-acetyltransfeases (NATs) seems complex. Vertebrate arylalkylamine N-acetyltransferase (aaNAT) has been extensively studied since it leads to the synthesis of melatonin, a multifunctional neurohormone prevalent in photoreceptor cells, and is known as a chemical token of the night. Melatonin also serves as a scavenger for reactive oxygen species. This is also true with invertebrates. NAT therefore has distinct functional implications in circadian function, as timezymes (aaNAT), and also xenobiotic reactions (arylamine NAT or simply NAT). NATs belong to a broader enzyme group, the GCN5-related N-acetyltransferase superfamily. Due to low sequence homology and a seemingly fast rate of structural differentiation, the nomenclature for NATs can be confusing. The advent of bioinformatics, however, has helped to classify this group of enzymes; vertebrates have two distinct subgroups, the timezyme type and the xenobiotic type, which has a wider substrate range including imidazolamine, pharmacological drugs, environmental toxicants and even histone. Insect aaNAT (iaaNAT) form their own clade in the phylogeny, distinct from vertebrate aaNATs. Arthropods are unique, since the phylum has exoskeleton in which quinones derived from N-acetylated monoamines function in coupling chitin and arthropodins. Monoamine oxidase (MAO) activity is limited in insects, but NAT-mediated degradation prevails. However, unexpectedly iaaNAT occurs not only among arthropods but also among basal deuterostomia, and is therefore more apomorphic. Our analyses illustrate that iaaNATs has unique physiological roles but at the same time it plays a role in a timezyme function, at least in photoperiodism. Photoperiodism has been considered as a function of circadian system but the detailed molecular mechanism is not well understood. We propose a molecular hypothesis for photoperiodism in Antheraea pernyi based on the transcription regulation of NAT interlocked by the circadian system. Therefore, the enzyme plays both unique and universal roles in insects. The unique role of iaaNATs in physiological regulation urges the targeting of this system for integrated pest management (IPM). We indeed showed a successful example of chemical compound screening with reconstituted enzyme and further attempts seem promising.
Collapse
Affiliation(s)
- Susumu Hiragaki
- Graduate School of Agricultural Science, Kobe UniversityKobe, Japan
| | - Takeshi Suzuki
- Department of Biology, The University of Western OntarioLondon, ON, Canada
| | | | - Makio Takeda
- Graduate School of Agricultural Science, Kobe UniversityKobe, Japan
| |
Collapse
|
7
|
Luo SL, Huang XJ, Wang Y, Jiang RW, Wang L, Bai LL, Peng QL, Song CL, Zhang DM, Ye WC. Isocoumarins from American cockroach (Periplaneta americana) and their cytotoxic activities. Fitoterapia 2014; 95:115-20. [PMID: 24631766 DOI: 10.1016/j.fitote.2014.03.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 02/26/2014] [Accepted: 03/02/2014] [Indexed: 11/16/2022]
Abstract
Four new isocoumarins (1-4), along with three known ones (5-7), were isolated from the 70% ethanol extract of the whole body of the traditional Chinese insect medicine, American cockroach (Periplaneta americana). The structures with absolute configurations of new compounds were elucidated by extensive spectroscopic methods in combination with X-ray diffraction experiment and CD analyses. Compounds 3-5 showed significant cytotoxic activities in HepG2 and MCF-7 cells with IC50 values in the ranges 6.41-23.91 μM and 6.67-39.07 μM, respectively.
Collapse
Affiliation(s)
- Shi-Lin Luo
- Department of Phytochemistry, China Pharmaceutical University, Nanjing 210009, PR China; Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, PR China; JNU-HKUST Joint Laboratory for Neuroscience & Innovative Drug Research, College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Xiao-Jun Huang
- Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, PR China; JNU-HKUST Joint Laboratory for Neuroscience & Innovative Drug Research, College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Ying Wang
- Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, PR China; JNU-HKUST Joint Laboratory for Neuroscience & Innovative Drug Research, College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Ren-Wang Jiang
- Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Lei Wang
- Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, PR China; JNU-HKUST Joint Laboratory for Neuroscience & Innovative Drug Research, College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Liang-Liang Bai
- Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Qun-Long Peng
- Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Cai-Lu Song
- Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, PR China; JNU-HKUST Joint Laboratory for Neuroscience & Innovative Drug Research, College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Dong-Mei Zhang
- Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, PR China.
| | - Wen-Cai Ye
- Department of Phytochemistry, China Pharmaceutical University, Nanjing 210009, PR China; Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, PR China; JNU-HKUST Joint Laboratory for Neuroscience & Innovative Drug Research, College of Pharmacy, Jinan University, Guangzhou 510632, PR China.
| |
Collapse
|
8
|
A visible dominant marker for insect transgenesis. Nat Commun 2013; 3:1295. [PMID: 23250425 PMCID: PMC3535423 DOI: 10.1038/ncomms2312] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 11/21/2012] [Indexed: 11/23/2022] Open
Abstract
Transgenesis of most insects currently relies on fluorescence markers. Here we establish a transformation marker system causing phenotypes visible to the naked eye due to changes in the color of melanin pigments, which are widespread in animals. Ubiquitous overexpression of arylalkylamine-N-acetyl transferase in the silkworm, Bombyx mori, changes the color of newly hatched first-instar larvae from black to a distinctive light brown color, and can be used as a molecular marker by directly connecting to baculovirus immediate early 1 gene promoter. Suppression of black pigmentation by Bm-arylalkylamine-N-acetyl transferase can be observed throughout the larval stages and in adult animals. Alternatively, overexpression in another gene, B. mori β-alanyl-dopamine synthetase (Bm-ebony), changes the larval body color of older instars, although first-instar larvae had normal dark coloration. We further show that ectopic Bm-arylalkylamine-N-acetyl transferase expression lightens coloration in ladybird beetle Harmonia axyridis and fruit fly Drosophila melanogaster, highlighting the potential usefulness of this marker for transgenesis in diverse insect taxa. Genetic modification in insects mostly involves the use of fluorescent markers to identify successful transformation. Here Osanai-Futahashi et al. report a marker system based on changes in melanin pigmentation that allows the identification of genetically modified insects with the naked eye.
Collapse
|
9
|
Tsugehara T, Imai T, Takeda M. Characterization of arylalkylamine N-acetyltransferase from silkmoth (Antheraea pernyi) and pesticidal drug design based on the baculovirus-expressed enzyme. Comp Biochem Physiol C Toxicol Pharmacol 2013; 157:93-102. [PMID: 23064182 DOI: 10.1016/j.cbpc.2012.10.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 10/03/2012] [Accepted: 10/04/2012] [Indexed: 10/27/2022]
Abstract
Arylalkylamine N-acetyltransferase (AANAT; EC 2.3.1.87) catalyzes the N-acetylation of arylalkylamines. A cDNA encoding AANAT (ApAANAT) was cloned from Antheraea pernyi by PCR. The cDNA of 1966 bp encodes a 261 amino acid protein. The amino acid sequence was found to have a high homology with Bombyx mori AANAT (BmNAT) but had very low homology with vertebrate AANATs. Amino acid sequence analysis revealed that four insect AANATs cloned from three species including ApAANAT formed a distinct cluster from the vertebrate group. A recombinant ApAANAT protein was expressed in Sf9 cells using a baculovirus expression system, having AANAT activity. The transformed cell extract acetylated tryptamine, serotonin, dopamine, tyramine, octopamine and norepinephrine. The AANAT activity was inhibited at over 0.03 mM tryptamine. Although insect AANATs have been considered as a target of insecticide, this type of insecticide has never been developed. Screening a chemical library of Otsuka Chemical Co., Ltd., we found a novel compound and its derivatives that inhibited the AANAT activity of ApAANAT. This may facilitate investigation of the monoamine metabolic pathway in insects and the development of new types of insecticides and inhibitors of AANATs.
Collapse
Affiliation(s)
- Taketo Tsugehara
- Graduate School of Natural Science and Technology, Kobe University, Rokkodai-cho, Nadaku, Japan
| | | | | |
Collapse
|
10
|
Mehere P, Han Q, Christensen BM, Li J. Identification and characterization of two arylalkylamine N-acetyltransferases in the yellow fever mosquito, Aedes aegypti. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2011; 41:707-14. [PMID: 21645618 PMCID: PMC3576024 DOI: 10.1016/j.ibmb.2011.05.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 05/11/2011] [Accepted: 05/13/2011] [Indexed: 05/03/2023]
Abstract
In this study we provide a molecular and biochemical identification of two arylalkylamine N-acetyltransferases (aaNAT) from Aedes aegypti mosquitoes. N-acetyldopamine, the enzyme product of aaNAT, was detected in Ae. aegypti, indicating the presence of an aaNAT in this mosquito. A BLAST search of the Ae. aegypti genome, using sequence information from an activity-verified Drosophila aaNAT, identified thirteen putative aaNAT sequences sharing 13-48% sequence identity with the Drosophila enzyme. Eight of the thirteen putative aaNAT proteins were expressed using a bacterial expression system. Screening of purified recombinant proteins against 5-hydroxytryptamine, dopamine, methoxytryptamine, norepinephrine, octopamine, tryptamine, and tyramine substrates, established that two of the putative aaNATs are active to the tested arylalkylamines. We therefore named them aaNAT1 and 2, respectively. Analysis of the transcriptional profiles of the two aaNAT genes from Ae. aegypti revealed that aaNAT1 is more abundant in the whole body of larvae and pupae, and aaNAT2 is more abundant in the head of adult mosquitoes. Based on their substrate and transcriptional profiles, together with previous reports from other insects, we suggest that the two aaNATs play diverse roles in Ae. aegypti, with aaNAT1 primarily involved in sclerotization and aaNAT2 mainly in neurotransmitter inactivation. Our data provide a beginning to a more comprehensive understanding of the biochemistry and physiology of aaNATs from the Ae. aegypti and serve as a reference for studying the aaNAT family of proteins from other insect species.
Collapse
Affiliation(s)
| | - Qian Han
- Department of Biochemistry, Virginia Tech, Blacksburg, VA, USA
| | - Bruce M. Christensen
- Department of Pathobiological Sciences, University of Wisconsin-Madison, WI 53706
| | - Jianyong Li
- Department of Biochemistry, Virginia Tech, Blacksburg, VA, USA
- Corresponding author: Jianyong Li: Tel: 540-231-1182; Fax: 540-231-9070;
| |
Collapse
|
11
|
Tsugehara T, Iwai S, Fujiwara Y, Mita K, Takeda M. Cloning and characterization of insect arylalkylamine N-acetyltransferase from Bombyx mori. Comp Biochem Physiol B Biochem Mol Biol 2007; 147:358-66. [PMID: 17449311 DOI: 10.1016/j.cbpb.2006.10.112] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2005] [Revised: 10/09/2006] [Accepted: 10/25/2006] [Indexed: 10/23/2022]
Abstract
Arylalkylamine N-acetyltransferase (AANAT) catalyzes N-acetylation of arylarkylamines. A cDNA of Bombyx mori insect AANAT (Bm-iAANAT) was found by searching an expressed-sequence tag (EST) database of B. mori (SilkBase). The cDNA encoded a 261 amino acid protein. The mRNA of Bm-iAANAT was expressed in eggs, larvae, adults and various tissues. Recombinant Bm-iAANAT protein was expressed in Sf9 cells by a baculovirus expression system. The AANAT activity of Bm-iAANAT was inhibited by high concentrations (over 0.01 mM) of tryptamine used as a substrate. The Bm-iAANAT acetylated tryptamine, serotonin, dopamine, octopamine, tyramine and norepinephrine. This is the first report of a cloned AANAT that acetylated norepinephrine. These results suggest that Bm-iAANAT is a novel member of insect AANAT family with unique kinetic properties and a broad substrate range.
Collapse
Affiliation(s)
- Taketo Tsugehara
- Division of Molecular Science, Graduate School of Science and Technology, Kobe University, Kobe, Hyogo, Japan
| | | | | | | | | |
Collapse
|