Ptch receptors 1 and 2 mediate Hedgehog signaling pivotal for organ development and homeostasis. In contrast to embryonic lethal Ptch1 -/- phenotype, Ptch2 -/- mice display no effect on gross phenotype. In this brief report, we provide evidence of changes in the putative incisor mesenchymal stem cell (MSC) niches that contribute to accelerated incisor growth, as well as intriguing changes in the bones and skin which suggest a role for Ptch2 in the regulation of MSCs and their regenerative potential. We employed histological, immunostaining, and computed tomography (µCT) analyses to analyze morphological differences between Ptch2 -/- and wild-type incisors, long bones, and skins. In vitro CFU and differentiation assays were used to demonstrate the MSC content and differentiation potential of Ptch2 -/- bone marrow stromal cells. Wound healing assay was performed in vivo and in vitro on 8-week-old mice to assess the effect of Ptch2 on the wound closure. Loss of Ptch2 causes increases in the number of putative MSCs in the continuously growing incisor, associated with increased vascularization observed in the tooth mesenchyme and the neurovascular bundle. Increased length and volume of Ptch2 -/- bones is linked with the increased number and augmented in vitro differentiation potential of MSCs in the bone marrow. Dynamic changes in the Ptch2 -/- skin thickness relate to changes in the mesenchymal compartment and impact the wound closure potential. The effects of Ptch2 abrogation on the postnatal MSCs suggest a crucial role for Ptch2 in Hedgehog signaling regulation of the organ regenerative potential.

Cell and Tissue Dynamics Research Program Institute of Biotechnology HiLIFE University of Helsinki Helsinki Finland

Circuar Economy Solutions Unit Geological Survey of Finland Espoo Finland

Department of Anthropology National Museum of Nature and Science Taito Japan

Department of Experimental Biology Faculty of Science Masaryk University Brno Czechia

Department of Genetics St Jude Children's Research Hospital Memphis TN United States

Institute of Animal Physiology and Genetics CAS Brno Czechia

Institute of Oral Biology Centre for Dental Medicine University of Zürich Zürich Switzerland

Oral and Maxillofacial Diseases Helsinki University Hospital Helsinki Finland

Orthodontics Oral and Maxillofacial Diseases University of Helsinki Helsinki Finland

Zobrazit více v PubMed

Adolphe C., Nieuwenhuis E., Villani R., Li Z. J., Kaur P., Hui C.-c., et al. (2014). Patched 1 and Patched 2 Redundancy Has a Key Role in Regulating Epidermal Differentiation. J. Invest. Dermatol. 134 (7), 1981–1990. 10.1038/jid.2014.63 PubMed DOI

Alfaro A. C., Roberts B., Kwong L., Bijlsma M. F., Roelink H. (2014). Ptch2 Mediates the Shh Response in Ptch1−/− Cells. Development 141 (17), 3331–3339. 10.1242/dev.110056 PubMed DOI PMC

Alonso L., Fuchs E. (2006). The Hair Cycle. J. Cel Sci 119 (Pt 3), 391–393. 10.1242/jcs02793 PubMed DOI

Ambrosi T. H., Longaker M. T., Chan C. K. F. (2019). A Revised Perspective of Skeletal Stem Cell Biology. Front. Cel Dev. Biol. 7, 189. 10.3389/fcell.2019.00189 PubMed DOI PMC

Aragona M., Blanpain C. (2017). Transgenic Stem Cells Replace Skin. Nature 551 (7680), 306–307. 10.1038/nature24753 PubMed DOI

Aragona M., Dekoninck S., Rulands S., Lenglez S., Mascré G., Simons B. D., et al. (2017). Defining Stem Cell Dynamics and Migration during Wound Healing in Mouse Skin Epidermis. Nat. Commun. 8, 14684. 10.1038/ncomms14684 PubMed DOI PMC

Bajestan S. N., Umehara F., Shirahama Y., Itoh K., Sharghi-Namini S., Jessen K. R., et al. (2006). Desert Hedgehog-Patched 2 Expression in Peripheral Nerves during Wallerian Degeneration and Regeneration. J. Neurobiol. 66 (3), 243–255. 10.1002/neu.20216 PubMed DOI

Balic A., Aguila H. L., Caimano M. J., Francone V. P., Mina M. (2010). Characterization of Stem and Progenitor Cells in the Dental Pulp of Erupted and Unerupted Murine Molars. Bone 46 (6), 1639–1651. 10.1016/j.bone.2010.02.019 PubMed DOI PMC

Balic A. (20191922). Isolation of Dental Stem Cell-Enriched Populations from Continuously Growing Mouse Incisors. Methods Mol. Biol., 29–37. 10.1007/978-1-4939-9012-2_4 PubMed DOI

Biggs L. C., Goudy S. L., Dunnwald M. (2015). Palatogenesis and Cutaneous Repair: A Two-Headed coin. Dev. Dyn. 244 (3), 289–310. 10.1002/dvdy.24224 PubMed DOI PMC

Binder M., Chmielarz P., McKinnon P. J., Biggs L. C., Thesleff I., Balic A. (2019). Functionally Distinctive Ptch Receptors Establish Multimodal Hedgehog Signaling in the Tooth Epithelial Stem Cell Niche. Stem Cells 37 (9), 1238–1248. 10.1002/stem.3042 PubMed DOI PMC

Byrd N., Grabel L. (2004). Hedgehog Signaling in Murine Vasculogenesis and Angiogenesis. Trends Cardiovasc. Med. 14 (8), 308–313. 10.1016/j.tcm.2004.09.003 PubMed DOI

Deng Q., Li P., Che M., Liu J., Biswas S., Ma G., et al. (2019). Activation of Hedgehog Signaling in Mesenchymal Stem Cells Induces Cartilage and Bone Tumor Formation via Wnt/β-Catenin. Elife 8. 10.7554/eLife.50208 PubMed DOI PMC

Feng J., Mantesso A., De Bari C., Nishiyama A., Sharpe P. T. (2011). Dual Origin of Mesenchymal Stem Cells Contributing to Organ Growth and Repair. Proc. Natl. Acad. Sci. U.S.A. 108 (16), 6503–6508. 10.1073/pnas.1015449108 PubMed DOI PMC

Goodrich L. V., Milenković L., Higgins K. M., Scott M. P. (1997). Altered Neural Cell Fates and Medulloblastoma in Mouse Patched Mutants. Science 277 (5329), 1109–1113. 10.1126/science.277.5329.1109 PubMed DOI

Hansen L. S., Coggle J. E., Wells J., Charles M. W. (1984). The Influence of the Hair Cycle on the Thickness of Mouse Skin. Anat. Rec. 210 (4), 569–573. 10.1002/ar.1092100404 PubMed DOI

Holtz A. M., Peterson K. A., Nishi Y., Morin S., Song J. Y., Charron F., et al. (2013). Essential Role for Ligand-dependent Feedback Antagonism of Vertebrate Hedgehog Signaling by PTCH1, PTCH2 and HHIP1 during Neural Patterning. Development 140 (16), 3423–3434. 10.1242/dev.095083 PubMed DOI PMC

Hui C.-c., Angers S. (2011). Gli Proteins in Development and Disease. Annu. Rev. Cel Dev. Biol. 27, 513–537. 10.1146/annurev-cellbio-092910-154048 PubMed DOI

Jensen E. C. (2013). Quantitative Analysis of Histological Staining and Fluorescence Using ImageJ. Anat. Rec. 296 (3), 378–381. 10.1002/ar.22641 PubMed DOI

Joost S., Annusver K., Jacob T., Sun X., Dalessandri T., Sivan U., et al. (2020). The Molecular Anatomy of Mouse Skin during Hair Growth and Rest. Cell Stem Cell 26 (3), 441–457. 10.1016/j.stem.2020.01.012 PubMed DOI

Kaukua N., Shahidi M. K., Konstantinidou C., Dyachuk V., Kaucka M., Furlan A., et al. (2014). Glial Origin of Mesenchymal Stem Cells in a Tooth Model System. Nature 513 (7519), 551–554. 10.1038/nature13536 PubMed DOI

Kim Y., Lee J., Seppala M., Cobourne M. T., Kim S.-H. (2020). Ptch2/Gas1 and Ptch1/Boc Differentially Regulate Hedgehog Signalling in Murine Primordial Germ Cell Migration. Nat. Commun. 11 (1), 1994. 10.1038/s41467-020-15897-3 PubMed DOI PMC

Klein C., Zwick A., Kissel S., Forster C. U., Pfeifer D., Follo M., et al. (2016). Ptch2 Loss Drives Myeloproliferation and Myeloproliferative Neoplasm Progression. J. Exp. Med. 213 (2), 273–290. 10.1084/jem.20150556 PubMed DOI PMC

Kong J. H., Siebold C., Rohatgi R. (2019). Biochemical Mechanisms of Vertebrate Hedgehog Signaling. Development 146 (10). 10.1242/dev.166892 PubMed DOI PMC

Krivanek J., Soldatov R. A., Kastriti M. E., Chontorotzea T., Herdina A. N., Petersen J., et al. (2020). Dental Cell Type Atlas Reveals Stem and Differentiated Cell Types in Mouse and Human Teeth. Nat. Commun. 11 (1), 4816. 10.1038/s41467-020-18512-7 PubMed DOI PMC

Lavine K. J., Long F., Choi K., Smith C., Ornitz D. M. (2008). Hedgehog Signaling to Distinct Cell Types Differentially Regulates Coronary Artery and Vein Development. Development 135 (18), 3161–3171. 10.1242/dev.019919 PubMed DOI PMC

Lee Y., Miller H. L., Russell H. R., Boyd K., Curran T., McKinnon P. J. (2006). Patched2 Modulates Tumorigenesis in Patched1 Heterozygous Mice. Cancer Res. 66 (14), 6964–6971. 10.1158/0008-5472.CAN-06-0505 PubMed DOI

Li J., Wang C., Pan Y., Bai Z., Wang B. (2011). Increased Proteolytic Processing of Full-Length Gli2 Transcription Factor Reduces the Hedgehog Pathway Activity In Vivo . Dev. Dyn. 240 (4), 766–774. 10.1002/dvdy.22578 PubMed DOI PMC

Lim C. H., Sun Q., Ratti K., Lee S.-H., Zheng Y., Takeo M., et al. (2018). Hedgehog Stimulates Hair Follicle Neogenesis by Creating Inductive Dermis during Murine Skin Wound Healing. Nat. Commun. 9 (1), 4903. 10.1038/s41467-018-07142-9 PubMed DOI PMC

Mardaryev A. N., Meier N., Poterlowicz K., Sharov A. A., Sharova T. Y., Ahmed M. I., et al. (2011). Lhx2 Differentially Regulates Sox9, Tcf4 and Lgr5 in Hair Follicle Stem Cells to Promote Epidermal Regeneration after Injury. Development 138 (22), 4843–4852. 10.1242/dev.070284 PubMed DOI PMC

Motoyama J., Takabatake T., Takeshima K., Hui C.-c. (1998). Ptch2, a Second Mouse Patched Gene Is Co-expressed with Sonic Hedgehog. Nat. Genet. 18 (2), 104–106. 10.1038/ng0298-104 PubMed DOI

Nieuwenhuis E., Motoyama J., Barnfield P. C., Yoshikawa Y., Zhang X., Mo R., et al. (2006). Mice with a Targeted Mutation of Patched2 Are Viable but Develop Alopecia and Epidermal Hyperplasia. Mol. Cel Biol 26 (17), 6609–6622. 10.1128/MCB.00295-06 PubMed DOI PMC

Pan Y., Bai C. B., Joyner A. L., Wang B. (2006). Sonic Hedgehog Signaling Regulates Gli2 Transcriptional Activity by Suppressing its Processing and Degradation. Mol. Cel Biol 26 (9), 3365–3377. 10.1128/MCB.26.9.3365-3377.2006 PubMed DOI PMC

Parmantier E., Lynn B., Lawson D., Turmaine M., Namini S. S., Chakrabarti L., et al. (1999). Schwann Cell-Derived Desert Hedgehog Controls the Development of Peripheral Nerve Sheaths. Neuron 23 (4), 713–724. 10.1016/s0896-6273(01)80030-1 PubMed DOI

Rhee H., Polak L., Fuchs E. (2006). Lhx2 Maintains Stem Cell Character in Hair Follicles. Science 312 (5782), 1946–1949. 10.1126/science.1128004 PubMed DOI PMC

Roberts B., Casillas C., Alfaro A. C., Jägers C., Roelink H. (2016). Patched1 and Patched2 Inhibit Smoothened Non-cell Autonomously. Elife 5. 10.7554/eLife.17634 PubMed DOI PMC

Schneider R. K., Mullally A., Dugourd A., Peisker F., Hoogenboezem R., Van Strien P. M. H., et al. (2017). Gli1 + Mesenchymal Stromal Cells Are a Key Driver of Bone Marrow Fibrosis and an Important Cellular Therapeutic Target. Cell Stem Cell 20 (6), 785–800. 10.1016/j.stem.2017.03.008 PubMed DOI PMC

Sharghi-Namini S., Turmaine M., Meier C., Sahni V., Umehara F., Jessen K. R., et al. (2006). The Structural and Functional Integrity of Peripheral Nerves Depends on the Glial-Derived Signal Desert Hedgehog. J. Neurosci. 26 (23), 6364–6376. 10.1523/JNEUROSCI.0157-06.2006 PubMed DOI PMC

Vidovic I., Banerjee A., Fatahi R., Matthews B. G., Dyment N. A., Kalajzic I., et al. (2017). Αsma-Expressing Perivascular Cells Represent Dental Pulp Progenitors In Vivo . J. Dent Res. 96 (3), 323–330. 10.1177/0022034516678208 PubMed DOI PMC

Yang W., Guo D., Harris M. A., Cui Y., Gluhak-Heinrich J., Wu J., et al. (2013). Bmp2 Gene in Osteoblasts of Periosteum and Trabecular Bone Links Bone Formation to Vascularization and Mesenchymal Stem Cells. J. Cel Sci 126 (Pt 18), 4085–4098. 10.1242/jcs.118596 PubMed DOI PMC

Zhao H., Feng J., Ho T.-V., Grimes W., Urata M., Chai Y. (2015). The Suture Provides a Niche for Mesenchymal Stem Cells of Craniofacial Bones. Nat. Cel Biol 17 (4), 386–396. 10.1038/ncb3139 PubMed DOI PMC

Zhao H., Feng J., Seidel K., Shi S., Klein O., Sharpe P., et al. (2014). Secretion of Shh by a Neurovascular Bundle Niche Supports Mesenchymal Stem Cell Homeostasis in the Adult Mouse Incisor. Cell Stem Cell 14 (2), 160–173. 10.1016/j.stem.2013.12.013 PubMed DOI PMC

Zhulyn O., Nieuwenhuis E., Liu Y. C., Angers S., Hui C.-c. (2015). Ptch2 Shares Overlapping Functions with Ptch1 in Smo Regulation and Limb Development. Dev. Biol. 397 (2), 191–202. 10.1016/j.ydbio.2014.10.023 PubMed DOI