Coordination of cell cycle and morphogenesis during organ formation
Abstract
Organ formation requires precise regulation of cell cycle and morphogenetic events. Using the Drosophila embryonic salivary gland (SG) as a model, we uncover the role of the SP1/KLF transcription factor Huckebein (Hkb) in coordinating cell cycle regulation and morphogenesis. The hkb mutant SG exhibits defects in invagination positioning and organ size due to abnormal death of SG cells. Normal SG development involves distal-to-proximal progression of endoreplication (endocycle), whereas hkb mutant SG cells undergo abnormal cell division, leading to cell death. Hkb represses the expression of key cell cycle and pro-apoptotic genes in the SG. Knockdown of cyclin E or cyclin-dependent kinase 1, or overexpression of fizzy-related rescues most of the morphogenetic defects observed in the hkb mutant SG. These results indicate that Hkb plays a critical role in controlling endoreplication by regulating the transcription of key cell cycle effectors to ensure proper organ formation.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting file.Supplementary file 3 contains all the full list of Hkb target genes, GO clusters, and the list of genes in each cluster.
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Identification of functional elements and regulatory circuits by Drosophila modENCODENCBI Gene Expression Omnibus, GSM569793.
Article and author information
Author details
Funding
National Science Foundation (MCB 2141387)
- SeYeon Chung
Louisiana Board of Regents (LEQSF(2019-22)-RD-A-04)
- SeYeon Chung
Louisiana State University
- SeYeon Chung
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2024, Matthew et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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