{"title":"Harderian Gland Development and Degeneration in the Fgf10- Deficient Heterozygous Mouse","authors":"Shiori Ikeda, Keita Sato, Hirofumi Fujita, Hitomi Ono-Minagi, Satoru Miyaishi, Tsutomu Nohno, Hideyo Ohuchi","doi":"10.3390/jdb12020016","DOIUrl":null,"url":null,"abstract":"The mouse Harderian gland (HG) is a secretory gland that covers the posterior portion of the eyeball, opening at the base of the nictitating membrane. The HG serves to protect the eye surface from infection with its secretions. Mice open their eyelids at about 2 weeks of age, and the development of the HG primordium mechanically opens the eye by pushing the eyeball from its rear. Therefore, when HG formation is disturbed, the eye exhibits enophthalmos (the slit-eye phenotype), and a line of Fgf10+/− heterozygous loss-of-function mice exhibits slit-eye due to the HG atrophy. However, it has not been clarified how and when HGs degenerate and atrophy in Fgf10+/− mice. In this study, we observed the HGs in embryonic (E13.5 to E19), postnatal (P0.5 to P18) and 74-week-old Fgf10+/− mice. We found that more than half of the Fgf10+/− mice had markedly degenerated HGs, often unilaterally. The degenerated HG tissue had a melanized appearance and was replaced by connective tissue, which was observed by P10. The development of HGs was delayed or disrupted in the similar proportion of Fgf10+/− embryos, as revealed via histology and the loss of HG-marker expression. In situ hybridization showed Fgf10 expression was observed in the Harderian mesenchyme in wild-type as well as in the HG-lacking heterozygote at E19. These results show that the Fgf10 haploinsufficiency causes delayed or defective HG development, often unilaterally from the unexpectedly early neonatal period.","PeriodicalId":15563,"journal":{"name":"Journal of Developmental Biology","volume":null,"pages":null},"PeriodicalIF":2.2000,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Developmental Biology","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.3390/jdb12020016","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"DEVELOPMENTAL BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
The mouse Harderian gland (HG) is a secretory gland that covers the posterior portion of the eyeball, opening at the base of the nictitating membrane. The HG serves to protect the eye surface from infection with its secretions. Mice open their eyelids at about 2 weeks of age, and the development of the HG primordium mechanically opens the eye by pushing the eyeball from its rear. Therefore, when HG formation is disturbed, the eye exhibits enophthalmos (the slit-eye phenotype), and a line of Fgf10+/− heterozygous loss-of-function mice exhibits slit-eye due to the HG atrophy. However, it has not been clarified how and when HGs degenerate and atrophy in Fgf10+/− mice. In this study, we observed the HGs in embryonic (E13.5 to E19), postnatal (P0.5 to P18) and 74-week-old Fgf10+/− mice. We found that more than half of the Fgf10+/− mice had markedly degenerated HGs, often unilaterally. The degenerated HG tissue had a melanized appearance and was replaced by connective tissue, which was observed by P10. The development of HGs was delayed or disrupted in the similar proportion of Fgf10+/− embryos, as revealed via histology and the loss of HG-marker expression. In situ hybridization showed Fgf10 expression was observed in the Harderian mesenchyme in wild-type as well as in the HG-lacking heterozygote at E19. These results show that the Fgf10 haploinsufficiency causes delayed or defective HG development, often unilaterally from the unexpectedly early neonatal period.
期刊介绍:
The Journal of Developmental Biology (ISSN 2221-3759) is an international, peer-reviewed, quick-refereeing, open access journal, which publishes reviews, research papers and communications on the development of multicellular organisms at the molecule, cell, tissue, organ and whole organism levels. Our aim is to encourage researchers to effortlessly publish their new findings or concepts rapidly in an open access medium, overseen by their peers. There is no restriction on the length of the papers; the full experimental details must be provided so that the results can be reproduced. Electronic files regarding the full details of the experimental procedure, if unable to be published in a normal way, can be deposited as supplementary material. Journal of Developmental Biology focuses on: -Development mechanisms and genetics -Cell differentiation -Embryonal development -Tissue/organism growth -Metamorphosis and regeneration of the organisms. It involves many biological fields, such as Molecular biology, Genetics, Physiology, Cell biology, Anatomy, Embryology, Cancer research, Neurobiology, Immunology, Ecology, Evolutionary biology.