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Hiraiwa S, Takeshita S, Terano T, Hayashi R, Suzuki K, Tajiri R, Kojima T. Unveiling the cell dynamics during the final shape formation of the tarsus in Drosophila adult leg by live imaging. Dev Genes Evol 2024:10.1007/s00427-024-00719-z. [PMID: 38977431 DOI: 10.1007/s00427-024-00719-z] [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: 03/01/2024] [Accepted: 07/01/2024] [Indexed: 07/10/2024]
Abstract
Organisms display a remarkable diversity in their shapes. Although substantial progress has been made in unraveling the mechanisms that govern cell fate determination during development, the mechanisms by which fate-determined cells give rise to the final shapes of organisms remain largely unknown. This study describes in detail the process of the final shape formation of the tarsus, which is near the distal tip of the adult leg, during the pupal stage in Drosophila melanogaster. Days-long live imaging revealed unexpectedly complicated cellular dynamics. The epithelial cells transiently form the intriguing structure, which we named the Parthenon-like structure. The basal surface of the epithelial cells and localization of the basement membrane protein initially show a mesh-like structure and rapidly shrink into the membranous structure during the formation and disappearance of the Parthenon-like structure. Furthermore, macrophage-like cells are observed moving around actively in the Parthenon-like structure and engulfing epithelial cells. The findings in this research are expected to significantly contribute to our understanding of the mechanisms involved in shaping the final structure of the adult tarsus.
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Affiliation(s)
- Shotaro Hiraiwa
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Biosciences Building 501, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba, 277-8562, Japan
| | - Shumpei Takeshita
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Biosciences Building 501, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba, 277-8562, Japan
| | - Tensho Terano
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Biosciences Building 501, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba, 277-8562, Japan
| | - Ryuhei Hayashi
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Biosciences Building 501, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba, 277-8562, Japan
| | - Koyo Suzuki
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Biosciences Building 501, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba, 277-8562, Japan
| | - Reiko Tajiri
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Biosciences Building 501, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba, 277-8562, Japan
- Present address: Laboratory for Extracellular Morphogenesis, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba-shi, Chiba, 263-8522, Japan
| | - Tetsuya Kojima
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Biosciences Building 501, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba, 277-8562, Japan.
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Li DZ, Duan SG, Yang RN, Yi SC, Liu A, Abdelnabby HE, Wang MQ. BarH1 regulates odorant-binding proteins expression and olfactory perception of Monochamus alternatus Hope. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2022; 140:103677. [PMID: 34763091 DOI: 10.1016/j.ibmb.2021.103677] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 10/22/2021] [Accepted: 11/05/2021] [Indexed: 06/13/2023]
Abstract
Insect odorant-binding proteins (OBPs) are a class of small soluble proteins that can be found in various tissues wherein binding and transport of small molecules are required. Thus, OBPs are not only involved in typical olfactory function by specific activities with odorants but also participate in other physiological processes in non-chemosensory tissues. To better understand the complex biological functions of OBPs, it is necessary to study the transcriptional regulation of their expression patterns. In this paper, an apparent gradient expression pattern of Obp19, that was highly and specifically expressed in antennae and played an essential role in the detection of camphene, was defined in the antennae of the Japanese pine sawyer. Further, the transcription factor BarH1, that also presented gradient expression pattern in antennae, was found to regulate expression of Obp19 directly through binding to its upstream DNA sequence. The condition of BarH1 gene silence, the gene expression levels of Obp19 significantly decreased. At the same time, additional olfactory genes also were regulated and thus influence camphene reception. These findings provide us an opportunity to incorporate Obps in the gene regulatory networks of insects, which contribute to a better understanding of the multiplicity and diversity of OBPs and the olfactory mediated behaviors.
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Affiliation(s)
- Dong-Zhen Li
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China; Lab. of Forest Pathogen Integrated Biology, Research Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing, 100091, PR China
| | - Shuang-Gang Duan
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Rui-Nan Yang
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Shan-Cheng Yi
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Ao Liu
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Hazem Elewa Abdelnabby
- Department of Plant Protection, Faculty of Agriculture, Benha University, Banha, Qalyubia, 13736, Egypt
| | - Man-Qun Wang
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China.
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Kojima T. Developmental mechanism of the tarsus in insect legs. CURRENT OPINION IN INSECT SCIENCE 2017; 19:36-42. [PMID: 28521941 DOI: 10.1016/j.cois.2016.11.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2016] [Revised: 11/16/2016] [Accepted: 11/22/2016] [Indexed: 06/07/2023]
Abstract
Insects show a tremendous morphological variety and have been a subject of studying morphological evolution. In legs, the tarsus is especially variable in the number of subsegments (tarsal segments) and their proportion unlike other leg segments. Recent studies in Drosophila melanogaster have revealed details of the tarsal development: regionalization of the tarsal region through integration of regulatory network and its growth, determination of the joint-forming region in each segment through strict regulation of Notch activity, changes in tissue morphology through regulation of RhoGTPases regulators and localized cell death, and finally, the morphogenetic mechanism of the ball-and-socket joint between tarsal segments. The substantial knowledge of the tarsal development makes it a suitable model for studying mechanisms of morphological evolution and diversification.
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Affiliation(s)
- Tetsuya Kojima
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.
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The bHLH-PAS transcription factor dysfusion regulates tarsal joint formation in response to Notch activity during drosophila leg development. PLoS Genet 2014; 10:e1004621. [PMID: 25329825 PMCID: PMC4199481 DOI: 10.1371/journal.pgen.1004621] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 07/19/2014] [Indexed: 01/22/2023] Open
Abstract
A characteristic of all arthropods is the presence of flexible structures called joints that connect all leg segments. Drosophila legs include two types of joints: the proximal or "true" joints that are motile due to the presence of muscle attachment and the distal joints that lack musculature. These joints are not only morphologically, functionally and evolutionarily different, but also the morphogenetic program that forms them is distinct. Development of both proximal and distal joints requires Notch activity; however, it is still unknown how this pathway can control the development of such homologous although distinct structures. Here we show that the bHLH-PAS transcription factor encoded by the gene dysfusion (dys), is expressed and absolutely required for tarsal joint development while it is dispensable for proximal joints. In the presumptive tarsal joints, Dys regulates the expression of the pro-apoptotic genes reaper and head involution defective and the expression of the RhoGTPases modulators, RhoGEf2 and RhoGap71E, thus directing key morphogenetic events required for tarsal joint development. When ectopically expressed, dys is able to induce some aspects of the morphogenetic program necessary for distal joint development such as fold formation and programmed cell death. This novel Dys function depends on its obligated partner Tango to activate the transcription of target genes. We also identified a dedicated dys cis-regulatory module that regulates dys expression in the tarsal presumptive leg joints through direct Su(H) binding. All these data place dys as a key player downstream of Notch, directing distal versus proximal joint morphogenesis.
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The zinc finger homeodomain-2 gene of Drosophila controls Notch targets and regulates apoptosis in the tarsal segments. Dev Biol 2013; 385:350-65. [PMID: 24144920 DOI: 10.1016/j.ydbio.2013.10.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2013] [Revised: 10/06/2013] [Accepted: 10/12/2013] [Indexed: 12/19/2022]
Abstract
The development of the Drosophila leg is a good model to study processes of pattern formation, cell death and segmentation. Such processes require the coordinate activity of different genes and signaling pathways that progressively subdivide the leg territory into smaller domains. One of the main pathways needed for leg development is the Notch pathway, required for determining the proximo-distal axis of the leg and for the formation of the joints that separate different leg segments. The mechanisms required to coordinate such events are largely unknown. We describe here that the zinc finger homeodomain-2 (zfh-2) gene is highly expressed in cells that will form the leg joints and needed to establish a correct size and pattern in the distal leg. There is an early requirement of zfh-2 to establish the correct proximo-distal axis, but zfh-2 is also needed at late third instar to form the joint between the fourth and fifth tarsal segments. The expression of zfh-2 requires Notch activity but zfh-2 is necessary, in turn, to activate Notch targets such as Enhancer of split and big brain. zfh-2 is controlled by the Drosophila activator protein 2 gene and regulates the late expression of tarsal-less. In the absence of zfh-2 many cells ectopically express the pro-apoptotic gene head involution defective, activate caspase-3 and are positive for acridine orange, indicating they undergo apoptosis. Our results demonstrate the key role of zfh-2 in the control of cell death and Notch signaling during leg development.
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Thanawala SU, Rister J, Goldberg GW, Zuskov A, Olesnicky EC, Flowers JM, Jukam D, Purugganan MD, Gavis ER, Desplan C, Johnston RJ. Regional modulation of a stochastically expressed factor determines photoreceptor subtypes in the Drosophila retina. Dev Cell 2013; 25:93-105. [PMID: 23597484 DOI: 10.1016/j.devcel.2013.02.016] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 12/07/2012] [Accepted: 02/25/2013] [Indexed: 10/27/2022]
Abstract
Stochastic mechanisms are sometimes utilized to diversify cell fates, especially in nervous systems. In the Drosophila retina, stochastic expression of the PAS-bHLH transcription factor Spineless (Ss) controls photoreceptor subtype choice. In one randomly distributed subset of R7 photoreceptors, Ss activates Rhodopsin4 (Rh4) and represses Rhodopsin3 (Rh3); counterparts lacking Ss express Rh3 and repress Rh4. In the dorsal third region of the retina, the Iroquois Complex transcription factors induce Rh3 in Rh4-expressing R7s. Here, we show that Ss levels are controlled in a binary on/off manner throughout the retina yet are attenuated in the dorsal third region to allow Rh3 coexpression with Rh4. Whereas the sensitivity of rh3 repression to differences in Ss levels generates stochastic and regionalized patterns, the robustness of rh4 activation ensures its stochastic expression throughout the retina. Our findings show how stochastic and regional inputs are integrated to control photoreceptor subtype specification in the Drosophila retina.
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Affiliation(s)
- Shivani U Thanawala
- Center for Developmental Genetics, Department of Biology, New York University, New York, NY 10003, USA
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Progressive tarsal patterning in the Drosophila by temporally dynamic regulation of transcription factor genes. Dev Biol 2012; 361:450-62. [DOI: 10.1016/j.ydbio.2011.10.031] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Revised: 10/24/2011] [Accepted: 10/25/2011] [Indexed: 10/15/2022]
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Wang JQ, Hou L, Yi N, Zhang RF, Zou XY, Xiao Q, Guo R. Molecular cloning and its expression of trachealess gene (As-trh) during development in brine shrimp, Artemia sinica. Mol Biol Rep 2011; 39:1659-65. [PMID: 21625858 DOI: 10.1007/s11033-011-0905-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Accepted: 05/18/2011] [Indexed: 12/12/2022]
Abstract
Basic helix-loop-helix-PAS (bHLH-PAS) family transcription factors are implicated in multiple developmental and physiological regulatory processes. Herein, a full-length cDNA encoding a bHLH-PAS domain transcription factor trachealess gene (designated as As-trh) was cloned and characterized from brine shrimp (Artemia sinica) for the first time. The full-length cDNA of As-trh was 2,698 bp with a 2,319 bp open reading frame encoding a deduced protein of 772 amino acid polypeptide with a calculated molecular mass of 86.02 kDa and an isoelectric point of 5.87. Sequence alignment revealed that As-trh had high homology with other species trh gene, including the D-trh gene in Drosophila melanogaster and Bm-trh in Bombyx mori. The early and persistent expression of As-trh in the naupliar stages by whole-mount embryonic in situ hybridization and immunohistochemistry suggest that As-trh functions very early in the salt gland and may be required continuously in this tissue. Later in development, expression of As-trh begins to decrease and disappear in salt gland of the older nauplius and appears in the thoracic epipods of the sub-adult Artemia. These results indicated that As-trh might play an important role in osmoregulatiory organ development from the larvae stages through adult stages.
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Affiliation(s)
- Jia-Qing Wang
- College of Ocean, Agricultural University of Hebei, Qinhuangdao 066003, People's Republic of China
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Morozova T, Hackett J, Sedaghat Y, Sonnenfeld M. The Drosophila jing gene is a downstream target in the Trachealess/Tango tracheal pathway. Dev Genes Evol 2010; 220:191-206. [PMID: 21061019 DOI: 10.1007/s00427-010-0339-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Accepted: 10/08/2010] [Indexed: 11/28/2022]
Abstract
Primary branching in the Drosophila trachea is regulated by the Trachealess (Trh) and Tango (Tgo) basic helix-loop-helix-PAS (bHLH-PAS) heterodimers, the POU protein Drifter (Dfr)/Ventral Veinless (Vvl), and the Pointed (Pnt) ETS transcription factor. The jing gene encodes a zinc finger protein also required for tracheal development. Three Trh/Tgo DNA-binding sites, known as CNS midline elements, in 1.5 kb of jing 5′ cis-regulatory sequence (jing1.5) previously suggested a downstream role for jing in the pathway. Here, we show that jing is a direct downstream target of Trh/Tgo and that Vvl and Pnt are also involved in jing tracheal activation. In vivo lacZ enhancer detection assays were used to identify cis-regulatory elements mediating embryonic expression patterns of jing. A 2.8-kb jing enhancer (jing2.8) drove lacZ expression in all tracheal cell lineages, the CNS midline and Engrailed-positive segmental stripes, mimicking endogenous jing expression. A 1.3-kb element within jing2.8 drove expression that was restricted to Engrailed-positive CNS midline cells and segmental ectodermal stripes. Surprisingly, jing1.5-lacZ expression was restricted to tracheal fusion cells despite the presence of consensus DNA-binding sites for bHLH-PAS, ETS, and POU domain transcription factors. Given the absence of Trh/Tgo DNA-binding sites in the jing1.3 enhancer, these results are consistent with previous observations suggesting a combinatorial basis to Trh-/Tgo-mediated transcriptional regulation in the trachea.
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Affiliation(s)
- Tatiana Morozova
- Faculty of Medicine, Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
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Sonnenfeld M, Morozova T, Hackett J, Sun X. Drosophila Jing is part of the breathless fibroblast growth factor receptor positive feedback loop. Dev Genes Evol 2010; 220:207-20. [PMID: 21061018 DOI: 10.1007/s00427-010-0342-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2010] [Accepted: 10/19/2010] [Indexed: 11/28/2022]
Abstract
In the developing Drosophila trachea, extensive cell migration lays the foundation for an elaborate network of tubules to form. This process is controlled by the Drosophila fibroblast growth factor receptor, known as Breathless (Btl), whose expression is activated by the Trachealess (Trh) and Tango (Tgo) basic helix-loop-helix (bHLH)-PAS transcription factors. We previously identified the jing zinc finger transcription factor as a gene sensitive to the dosage of bHLH-PAS transcriptional activity and showed that its mutations interact genetically with those of trh and btl. Here, we demonstrate that jing is required for btl expression in the branching trachea and dominantly interacts with known regulators of btl expression, including the ETS and POU transcription factors, pointed, and drifter/ventral veinless, respectively. Furthermore, the zinc finger-containing C-terminus of Jing associates with a btl tracheal enhancer in a Trh/Tgo-dependent manner in chromatin immunoprecipitation assays in vitro and interferes with btl in vitro and in vivo. Together, our results support a model by which Jing/Trh/Tgo complexes regulate btl transcript levels during primary tracheal branching.
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Affiliation(s)
- Margaret Sonnenfeld
- Faculty of Medicine, Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada.
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Adryan B, Teichmann SA. The developmental expression dynamics of Drosophila melanogaster transcription factors. Genome Biol 2010; 11:R40. [PMID: 20384991 PMCID: PMC2884543 DOI: 10.1186/gb-2010-11-4-r40] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Revised: 01/22/2010] [Accepted: 04/12/2010] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Site-specific transcription factors (TFs) are coordinators of developmental and physiological gene expression programs. Their binding to cis-regulatory modules of target genes mediates the precise cell- and context-specific activation and repression of genes. The expression of TFs should therefore reflect the core expression program of each cell. RESULTS We studied the expression dynamics of about 750 TFs using the available genomics resources in Drosophila melanogaster. We find that 95% of these TFs are expressed at some point during embryonic development, with a peak roughly between 10 and 12 hours after egg laying, the core stages of organogenesis. We address the differential utilization of DNA-binding domains in different developmental programs systematically in a spatio-temporal context, and show that the zinc finger class of TFs is predominantly early expressed, while Homeobox TFs exhibit later expression in embryogenesis. CONCLUSIONS Previous work, dissecting cis-regulatory modules during Drosophila development, suggests that TFs are deployed in groups acting in a cooperative manner. In contrast, we find that there is rapid exchange of co-expressed partners amongst the fly TFs, at rates similar to the genome-wide dynamics of co-expression clusters. This suggests there may also be a high level of combinatorial complexity of TFs at cis-regulatory modules.
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Affiliation(s)
- Boris Adryan
- Computational Biology Group, Structural Studies Division, MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK.
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Pueyo JI, Couso JP. The 11-aminoacid long Tarsal-less peptides trigger a cell signal in Drosophila leg development. Dev Biol 2008; 324:192-201. [PMID: 18801356 DOI: 10.1016/j.ydbio.2008.08.025] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Revised: 08/13/2008] [Accepted: 08/26/2008] [Indexed: 10/21/2022]
Abstract
The polycistronic and non-canonical gene tarsal-less encodes several short peptides 11 to 32 aminoacids long. tarsal-less is required for embryonic and imaginal development in Drosophila, but the molecular and cellular bases of its function are not known. Here we show that tarsal-less function triggers a cell signal. This signal has a range of 2-3 cells in Drosophila legs and may be provided directly by the Tarsal-less peptides. During leg development, this Tarsal-less signal implements the patterning activity of a tarsal boundary and regulates the transcription of several genes in a specific manner. Thus tarsal-less is necessary for the intercalation of the tarsal segments two to four and for the activation of the homeobox gene apterous, the Zinc-finger gene rotund and the bHLH-PAS gene spineless, and for the repression of the homeobox gene Bar and the putative transcription factor dacshund. These regulatory effects complement the known genetic scenario required for distal leg development and explain the requirements for tarsal-less in this process.
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Affiliation(s)
- Jose Ignacio Pueyo
- School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, UK
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Nishimura M, Inoue Y, Hayashi S. A wave of EGFR signaling determines cell alignment and intercalation in the Drosophila tracheal placode. Development 2007; 134:4273-82. [PMID: 17978004 DOI: 10.1242/dev.010397] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Invagination of organ placodes converts flat epithelia into three-dimensional organs. Cell tracing in the Drosophila tracheal placode revealed that, in the 30-minute period before invagination, cells enter mitotic quiescence and form short rows that encircle the future invagination site. The cells in the rows align to form a smooth boundary (;boundary smoothing'), accompanied by a transient increase in myosin at the boundary and cell intercalation oriented in parallel with the cellular rows. Cells then undergo apical constriction and invaginate, followed by radially oriented mitosis in the placode. Prior to invagination, ERK MAP kinase is activated in an outward circular wave, with the wave front often correlating with the smoothing cell boundaries. EGFR signaling is required for myosin accumulation and cell boundary smoothing, suggesting its propagation polarizes the planar cell rearrangement in the tracheal placode, and coordinates the timing and position of intrinsic cell internalization activities.
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Affiliation(s)
- Mayuko Nishimura
- Riken Center for Developmental Biology, 2-2-3 Minatojima-minamimachi, Kobe 650-0047, Japan
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