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Shainer I, Buchshtab A, Hawkins TA, Wilson SW, Cone RD, Gothilf Y. Novel hypophysiotropic AgRP2 neurons and pineal cells revealed by BAC transgenesis in zebrafish. Sci Rep 2017; 7:44777. [PMID: 28317906 PMCID: PMC5357965 DOI: 10.1038/srep44777] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 02/13/2017] [Indexed: 11/21/2022] Open
Abstract
The neuropeptide agouti-related protein (AgRP) is expressed in the arcuate nucleus of the mammalian hypothalamus and plays a key role in regulating food consumption and energy homeostasis. Fish express two agrp genes in the brain: agrp1, considered functionally homologous with the mammalian AgRP, and agrp2. The role of agrp2 and its relationship to agrp1 are not fully understood. Utilizing BAC transgenesis, we generated transgenic zebrafish in which agrp1- and agrp2-expressing cells can be visualized and manipulated. By characterizing these transgenic lines, we showed that agrp1-expressing neurons are located in the ventral periventricular hypothalamus (the equivalent of the mammalian arcuate nucleus), projecting throughout the hypothalamus and towards the preoptic area. The agrp2 gene was expressed in the pineal gland in a previously uncharacterized subgroup of cells. Additionally, agrp2 was expressed in a small group of neurons in the preoptic area that project directly towards the pituitary and form an interface with the pituitary vasculature, suggesting that preoptic AgRP2 neurons are hypophysiotropic. We showed that direct synaptic connection can exist between AgRP1 and AgRP2 neurons in the hypothalamus, suggesting communication and coordination between AgRP1 and AgRP2 neurons and, therefore, probably also between the processes they regulate.
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Affiliation(s)
- Inbal Shainer
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv, Israel
| | - Adi Buchshtab
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv, Israel
| | - Thomas A. Hawkins
- The Department of Cell and Developmental Biology, Faculty of Life Sciences, University College London, London, UK
| | - Stephen W. Wilson
- The Department of Cell and Developmental Biology, Faculty of Life Sciences, University College London, London, UK
| | - Roger D. Cone
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - Yoav Gothilf
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv, Israel
- Sagol School of Neuroscience, Tel-Aviv University, Tel-Aviv, Israel
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Rainy N, Etzion T, Alon S, Pomeranz A, Nisgav Y, Livnat T, Bach M, Gerstner CD, Baehr W, Gothilf Y, Stiebel-Kalish H. Knockdown of unc119c results in visual impairment and early-onset retinal dystrophy in zebrafish. Biochem Biophys Res Commun 2016; 473:1211-1217. [PMID: 27079236 DOI: 10.1016/j.bbrc.2016.04.041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 04/09/2016] [Indexed: 12/29/2022]
Abstract
PURPOSE UNC119 proteins are involved in G protein trafficking in mouse retinal photoreceptors and Caenorhabditis elegans olfactory neurons. An Unc119 null allele is associated with cone-rod dystrophy in mouse, but the mechanism leading to disease is not understood. We studied the role of Unc119 paralogs and Arl3l2 in zebrafish vision and retinal organization resulting from unc119c and arl3l2 knockdown. METHODS Zebrafish unc119c was amplified by PCR from retina and pineal gland cDNA. Its expression pattern in the eye and pineal gland was determined by whole-mount in-situ hybridization. unc119c and arl3l2 were knocked down using morpholino-modified oligonucleotides (MO). Their visual function was assessed with a quantitative optomotor assay on 6 days post-fertilization larvae. Retinal morphology was analyzed using immunohistochemistry with anti-cone arrestin (zpr-1) and anti-cone transducin-α (GNAT2) antibodies. RESULTS The zebrafish genome contains four genes encoding unc119 paralogs located on different chromosomes. The exon/intron arrangements of these genes are identical. Three Unc119 paralogs are expressed in the zebrafish retina, termed Unc119a-c. Based on sequence similarity, Unc119a and Unc119b are orthologs of mammalian UNC119a and UNC119b, respectively. A third, Unc119c, is unique and not present in mammals. Whole mount in-situ hybridization revealed that unc119a and unc119b RNA are ubiquitously expressed in the CNS, and unc119c is specifically expressed in photoreceptive tissues (pineal gland and retina). A Unc119 interactant, Arl3l2 also localizes to the pineal gland and the retina. As measured by the optomotor response, unc119c and arl3l2 knockdown resulted in significantly lower vision compared to wild-type zebrafish larvae and control morpholino (MO). Immunohistological analysis with anti-cone transducin and anti-cone arrestin (zpr-1) indicates that knockdown of unc119c leads to photoreceptor degeneration mostly affecting cones. CONCLUSIONS Our results suggest that Unc119c is the only Unc119 paralog that is highly specific to the retina in zebrafish. Unc119c and Arl3l2 proteins are important for the function of cones.
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Affiliation(s)
- Nir Rainy
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Israel
| | - Talya Etzion
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Israel
| | - Shahar Alon
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Israel; Sagol School of Neuroscience Tel Aviv University, Israel
| | - Adi Pomeranz
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Israel
| | - Yael Nisgav
- Laboratory of Eye Research, Felsenstein Medical Research Center Israel, Petah Tikva, Israel
| | - Tami Livnat
- Laboratory of Eye Research, Felsenstein Medical Research Center Israel, Petah Tikva, Israel
| | - Michael Bach
- Eye Center, Medical Center, University of Freiburg, Killianstraße 5, 79106, Freiburg, Germany
| | - Cecilia D Gerstner
- Department of Ophthalmology and Department of Neurobiology and Anatomy, University of Utah Health Science Center, Salt Lake City, UT 84132, USA
| | - Wolfgang Baehr
- Department of Ophthalmology and Department of Neurobiology and Anatomy, University of Utah Health Science Center, Salt Lake City, UT 84132, USA; Department of Biology, University of Utah, Salt Lake City, UT 84112, USA
| | - Yoav Gothilf
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Israel; Sagol School of Neuroscience Tel Aviv University, Israel
| | - Hadas Stiebel-Kalish
- Department of Ophthalmology at Rabin Medical Center, Petah Tikva & Sackler Faculty of Medicine, Tel Aviv University, Israel.
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McStay E, Migaud H, Vera LM, Sánchez-Vázquez FJ, Davie A. Comparative study of pineal clock gene and AANAT2 expression in relation to melatonin synthesis in Atlantic salmon (Salmo salar) and European seabass (Dicentrarchus labrax). Comp Biochem Physiol A Mol Integr Physiol 2013; 169:77-89. [PMID: 24361868 DOI: 10.1016/j.cbpa.2013.12.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Revised: 12/12/2013] [Accepted: 12/13/2013] [Indexed: 01/01/2023]
Abstract
The photoreceptive teleost pineal is considered to be essential to the generation, synchronisation and maintenance of biological rhythms, primarily via melatonin release. The role of internal (circadian clock) and external (light) signals controlling melatonin production in the fish pineal differs between species, yet the reasons underpinning this remain largely unknown. Whilst in salmonids, pineal melatonin is apparently regulated directly by light, in all other studied teleosts, rhythmic melatonin production persists endogenously under the regulation of clock gene expression. To better understand the role of clocks in teleost pineals, this study aimed to characterise the expression of selected clock genes in vitro under different photoperiodic conditions in comparison to in vivo in both Atlantic salmon (Salmo salar) and in European seabass (Dicentrarchus labrax) (in vitro 12L:12D), a species known to display endogenous rhythmic melatonin synthesis. Results revealed no rhythmic clock gene (Clock, Period 1 &2) expression in Atlantic salmon or European seabass (Clock and Period 1) pineal in vitro. However rhythmic expression of Cryptochrome 2 and Period 1 in the Atlantic salmon pineal was observed in vivo, which infers extra-pineal regulation of clocks in this species. No rhythmic arylalkylamine N-acetyltransferase 2 (Aanat2) expression was observed in the Atlantic salmon yet in the European seabass, circadian Aanat2 expression was observed. Subsequent in silico analysis of available Aanat2 genomic sequences reveals that Atlantic salmon Aanat2 promoter sequences do not contain similar regulatory architecture as present in European seabass, and previously described in other teleosts which alludes to a loss in functional connection in the pathway.
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Affiliation(s)
- Elsbeth McStay
- Institute of Aquaculture, University of Stirling, Stirling, Scotland FK9 4LA, UK
| | - Herve Migaud
- Institute of Aquaculture, University of Stirling, Stirling, Scotland FK9 4LA, UK
| | - Luisa Maria Vera
- University of Murcia, Department of Physiology, Regional Campus of International Excellence "Campus Mare Nostrum", Murcia 30100, Spain
| | - Francisco Javier Sánchez-Vázquez
- University of Murcia, Department of Physiology, Regional Campus of International Excellence "Campus Mare Nostrum", Murcia 30100, Spain
| | - Andrew Davie
- Institute of Aquaculture, University of Stirling, Stirling, Scotland FK9 4LA, UK.
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Smadja Storz S, Tovin A, Mracek P, Alon S, Foulkes NS, Gothilf Y. Casein kinase 1δ activity: a key element in the zebrafish circadian timing system. PLoS One 2013; 8:e54189. [PMID: 23349822 PMCID: PMC3549995 DOI: 10.1371/journal.pone.0054189] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2012] [Accepted: 12/11/2012] [Indexed: 01/07/2023] Open
Abstract
Zebrafish have become a popular model for studies of the circadian timing mechanism. Taking advantage of its rapid development of a functional circadian clock and the availability of light-entrainable clock-containing cell lines, much knowledge has been gained about the circadian clock system in this species. However, the post-translational modifications of clock proteins, and in particular the phosphorylation of PER proteins by Casein kinase I delta and epsilon (CK1δ and CK1ε), have so far not been examined in the zebrafish. Using pharmacological inhibitors for CK1δ and CK1ε, a pan-CK1δ/ε inhibitor PF-670462, and a CK1ε -selective inhibitor PF-4800567, we show that CK1δ activity is crucial for the functioning of the circadian timing mechanism of zebrafish, while CK1ε plays a minor role. The CK1δ/ε inhibitor disrupted circadian rhythms of promoter activity in the circadian clock-containing zebrafish cell line, PAC-2, while the CK1ε inhibitor had no effect. Zebrafish larvae that were exposed to the CK1δ/ε inhibitor showed no rhythms of locomotor activity while the CK1ε inhibitor had only a minor effect on locomotor activity. Moreover, the addition of the CK1δ/ε inhibitor disrupted rhythms of aanat2 mRNA expression in the pineal gland. The pineal gland is considered to act as a central clock organ in fish, delivering a rhythmic hormonal signal, melatonin, which is regulated by AANAT2 enzymatic activity. Therefore, CK1δ plays a key role in the circadian timing system of the zebrafish. Furthermore, the effect of CK1δ inhibition on rhythmic locomotor activity may reflect its effect on the function of the central clock in the pineal gland as well as its regulation of peripheral clocks.
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Affiliation(s)
- Sima Smadja Storz
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.
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Tovin A, Alon S, Ben-Moshe Z, Mracek P, Vatine G, Foulkes NS, Jacob-Hirsch J, Rechavi G, Toyama R, Coon SL, Klein DC, Eisenberg E, Gothilf Y. Systematic identification of rhythmic genes reveals camk1gb as a new element in the circadian clockwork. PLoS Genet 2012; 8:e1003116. [PMID: 23284293 PMCID: PMC3527293 DOI: 10.1371/journal.pgen.1003116] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Accepted: 10/11/2012] [Indexed: 11/18/2022] Open
Abstract
A wide variety of biochemical, physiological, and molecular processes are known to have daily rhythms driven by an endogenous circadian clock. While extensive research has greatly improved our understanding of the molecular mechanisms that constitute the circadian clock, the links between this clock and dependent processes have remained elusive. To address this gap in our knowledge, we have used RNA sequencing (RNA–seq) and DNA microarrays to systematically identify clock-controlled genes in the zebrafish pineal gland. In addition to a comprehensive view of the expression pattern of known clock components within this master clock tissue, this approach has revealed novel potential elements of the circadian timing system. We have implicated one rhythmically expressed gene, camk1gb, in connecting the clock with downstream physiology of the pineal gland. Remarkably, knockdown of camk1gb disrupts locomotor activity in the whole larva, even though it is predominantly expressed within the pineal gland. Therefore, it appears that camk1gb plays a role in linking the pineal master clock with the periphery. The circadian clock is a molecular pacemaker that drives rhythmic expression of genes with a ∼24-hour period. As a result, many physiological processes have daily rhythms. Many of the conserved elements that constitute the circadian clock are known, but the links between the clock and dependent processes have remained elusive. With its amenability to genetic manipulations and a variety of genetic tools, the zebrafish has become an attractive vertebrate model for the quest to identify and characterize novel clock components. Here, we take advantage of another attraction of the zebrafish, the fact that its pineal gland is the site of a central clock which directly receives light input and autonomously generates circadian rhythms that affect the physiology of the whole organism. We show that the systematic design and analysis of genome-wide experiments based on the zebrafish pineal gland can lead to the discovery of new clock elements. We have characterized one novel element, camk1gb, and show that this gene, predominantly expressed within the pineal gland and driven by the circadian clock, links circadian clock timing with locomotor activity in zebrafish larvae.
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Affiliation(s)
- Adi Tovin
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Shahar Alon
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Zohar Ben-Moshe
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Philipp Mracek
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Eggenstein, Germany
| | - Gad Vatine
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Nicholas S. Foulkes
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Eggenstein, Germany
| | - Jasmine Jacob-Hirsch
- Cancer Research Center, Sheba Medical Center, Tel Hashomer and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Gideon Rechavi
- Cancer Research Center, Sheba Medical Center, Tel Hashomer and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Reiko Toyama
- Laboratory of Molecular Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Steven L. Coon
- Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - David C. Klein
- Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Eli Eisenberg
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
- Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel
- * E-mail: (YG); (EE)
| | - Yoav Gothilf
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
- * E-mail: (YG); (EE)
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Ji C, Jin X, He J, Yin Z. Use of TSHβ:EGFP transgenic zebrafish as a rapid in vivo model for assessing thyroid-disrupting chemicals. Toxicol Appl Pharmacol 2012; 262:149-55. [PMID: 22571824 DOI: 10.1016/j.taap.2012.04.029] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Revised: 04/23/2012] [Accepted: 04/23/2012] [Indexed: 11/24/2022]
Abstract
Accumulating evidence indicates that a wide range of chemicals have the ability to interfere with the hypothalamic-pituitary-thyroid (HPT) axis. Novel endpoints should be evaluated in addition to existing methods in order to effectively assess the effects of these chemicals on the HPT axis. Thyroid-stimulating hormone subunit β (TSHβ) plays central regulatory roles in the HPT system. We identified the regulatory region that determines the expression level of zebrafish TSHβ in the anterior pituitary. In the transgenic zebrafish with EGFP driven by the TSHβ promoter, the similar responsive patterns between the expression levels of TSHβ:EGFP and endogenous TSHβ mRNA in the pituitary are observed following treatments with goitrogen chemicals and exogenous thyroid hormones (THs). These results suggest that the TSHβ:EGFP transgenic reporter zebrafish may be a useful alternative in vivo model for the assessment of chemicals interfering with the HPT system.
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Affiliation(s)
- Cheng Ji
- Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China
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Idda ML, Bertolucci C, Vallone D, Gothilf Y, Sánchez-Vázquez FJ, Foulkes NS. Circadian clocks. PROGRESS IN BRAIN RESEARCH 2012; 199:41-57. [DOI: 10.1016/b978-0-444-59427-3.00003-4] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Vatine G, Vallone D, Gothilf Y, Foulkes NS. It's time to swim! Zebrafish and the circadian clock. FEBS Lett 2011; 585:1485-94. [PMID: 21486566 DOI: 10.1016/j.febslet.2011.04.007] [Citation(s) in RCA: 200] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Revised: 04/03/2011] [Accepted: 04/04/2011] [Indexed: 01/07/2023]
Abstract
The zebrafish represents a fascinating model for studying key aspects of the vertebrate circadian timing system. Easy access to early embryonic development has made this species ideal for investigating how the clock is first established during embryogenesis. In particular, the molecular basis for the functional development of the zebrafish pineal gland has received much attention. In addition to this dedicated clock and photoreceptor organ, and unlike the situation in mammals, the clocks in zebrafish peripheral tissues and even cell lines are entrainable by direct exposure to light thus providing unique insight into the function and evolution of the light input pathway. Finally, the small size, low maintenance costs and high fecundity of this fish together with the availability of genetic tools make this an attractive model for forward genetic analysis of the circadian clock. Here, we review the work that has established the zebrafish as a valuable clock model organism and highlight the key questions that will shape the future direction of research.
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Affiliation(s)
- Gad Vatine
- Department of Neurobiology, George S. Wise Faculty of Life Sciences 52900, Tel Aviv University, Tel Aviv 69978, Israel
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Ben-Moshe Z, Vatine G, Alon S, Tovin A, Mracek P, Foulkes NS, Gothilf Y. Multiple PAR and E4BP4 bZIP transcription factors in zebrafish: diverse spatial and temporal expression patterns. Chronobiol Int 2011; 27:1509-31. [PMID: 20854132 DOI: 10.3109/07420528.2010.510229] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Circadian rhythms of physiology and behavior are generated by an autonomous circadian oscillator that is synchronized daily with the environment, mainly by light input. The PAR subfamily of transcriptional activators and the related E4BP4 repressor belonging to the basic leucine zipper (bZIP) family are clock-controlled genes that are suggested to mediate downstream circadian clock processes and to feedback onto the core oscillator. Here, the authors report the characterization of these genes in the zebrafish, an increasingly important model in the field of chronobiology. Five novel PAR and six novel e4bp4 zebrafish homolog genes were identified using bioinformatic tools and their coding sequences were cloned. Based on their evolutionary relationships, these genes were annotated as ztef2, zhlf1 and zhlf2, zdbp1 and zdbp2, and ze4bp4-1 to -6. The spatial and temporal mRNA expression pattern of each of these factors was characterized in zebrafish embryos in the context of a functional circadian clock and regulation by light. Nine of the factors exhibited augmented and rhythmic expression in the pineal gland, a central clock organ in zebrafish. Moreover, these genes were found to be regulated, to variable extents, by the circadian clock and/or by light. Differential expression patterns of multiple paralogs in zebrafish suggest multiple roles for these factors within the vertebrate circadian clock. This study, in the genetically accessible zebrafish model, lays the foundation for further research regarding the involvement and specific roles of PAR and E4BP4 transcription factors in the vertebrate circadian clock mechanism.
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Affiliation(s)
- Zohar Ben-Moshe
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv, Israel
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Klein DC, Bailey MJ, Carter DA, Kim JS, Shi Q, Ho AK, Chik CL, Gaildrat P, Morin F, Ganguly S, Rath MF, Møller M, Sugden D, Rangel ZG, Munson PJ, Weller JL, Coon SL. Pineal function: impact of microarray analysis. Mol Cell Endocrinol 2010; 314:170-83. [PMID: 19622385 PMCID: PMC3138125 DOI: 10.1016/j.mce.2009.07.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2009] [Accepted: 07/14/2009] [Indexed: 02/06/2023]
Abstract
Microarray analysis has provided a new understanding of pineal function by identifying genes that are highly expressed in this tissue relative to other tissues and also by identifying over 600 genes that are expressed on a 24-h schedule. This effort has highlighted surprising similarity to the retina and has provided reason to explore new avenues of study including intracellular signaling, signal transduction, transcriptional cascades, thyroid/retinoic acid hormone signaling, metal biology, RNA splicing, and the role the pineal gland plays in the immune/inflammation response. The new foundation that microarray analysis has provided will broadly support future research on pineal function.
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Affiliation(s)
- David C Klein
- Section on Neuroendocrinology, Program on Developmental Endocrinology and Genetics, NICHD, National Institutes of Health, Bethesda, MD 20892, USA.
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