Biology subjects

Klingler, M.

Publications and source records attributed to Klingler, M..

3 recordsLinked to original sources

bioRxiv2021

Large portion of essential genes is missed by screening either fly or beetle indicating unexpected diversity of insect gene function

Most gene functions were detected by screens in very few model organisms but it has remained unclear how comprehensive these data are. Here, we expanded our RNAi screen in the red flour beetle Tribolium castaneum to cover more than half of the protein-coding genes and we compared the gene sets involved in several processes between beetle and fly. We find that around 50 % of the gene functions are detected in both species while the rest was found only in fly (~10%) or beetle (~40%) reflecting both technical and biological differences. We conclude that work in complementary model systems is required to gain a comprehensive picture on gene functions documented by the annotation of novel GO terms for 96 genes studied here. The RNAi screening resources developed in this project, the expanding transgenic tool-kit and our large-scale functional data make T. castaneum an excellent model system in that endeavor.

genetics↗

bioRxiv2018

millepattes micropeptides are an ancient developmental switch required for embryonic patterning

Small open reading frames (smORFs) that code for \"micropeptides\" (10-100 amino acids) exhibit remarkable evolutionary complexity. Conserved micropeptides encoded by the millepattes (mlpt) gene are essential in Tribolium for embryogenesis but in Drosophila, function only in leg and cuticle differentiation. We find that a module identified in Drosophila trichome patterning, comprising Mlpt, UBR3, and Shaven-baby (Svb), coordinates early embryo patterning in several insect orders. Intriguingly, Mlpt segmentation function can be re-awakened in the Drosophila blastoderm, demonstrating the potency of an ancestral developmental switch retained despite evolving embryonic patterning modes. smORFs like millepattes thus illustrate plasticity of micropeptide functions despite constraints of essential genetic networks.\n\nOne sentence summaryA module comprising the small ORFs mlpt/pri/tal, the transcription factor Svb, and the ubiquitin ligase UBR3, possesses an ancestral function in insect embryo patterning which is lost in flies but reactivated when Svb expression is restored.

developmental biology↗

bioRxiv2018

A re-inducible genetic cascade patterns the anterior-posterior axis of insects in a threshold-free fashion

Gap genes mediate the division of the anterior-posterior axis of insects into different fates through regulating downstream hox genes. Decades of tinkering the segmentation gene network of the long-germ fruit fly Drosophila melanogaster led to the conclusion that gap genes are regulated (at least initially) through a threshold-based French Flag model, guided by both anteriorly- and posteriorly-localized morphogen gradients. In this paper, we show that the expression patterns of gap genes in the intermediate-germ beetle Tribolium castaneum are mediated by a threshold-free Speed Regulation mechanism, in which the speed of a genetic cascade of gap genes is regulated by a posterior gradient of the transcription factor Caudal. We show this by re-inducing the leading gap gene (namely, hunchback) resulting in the re-induction of the gap gene cascade at arbitrary points in time. This demonstrates that the gap gene network is self-regulatory and is primarily under the control of a posterior speed regulator in Tribolium and possibly all insects.

developmental biology↗