Large transgene arrays cause aberrant transcription and synthetic molting defects
- 1Friedrich Miescher Institute for Biomedical Research (FMI) , 4056 Basel ,
- 2SIB Swiss Institute of Bioinformatics , 4056 Basel ,
- 3University of Basel , 4056 Basel ,
Abstract
Multicopy transgene arrays remain widely used in Caenorhabditis elegans research. It is usually assumed that they behave neutrally, not impacting the phenotype under investigation. Here, we reveal that a previously reported heterochronic extra-molt phenotype associated with myrf-1(mg412) depends on the presence of the integrated molting reporter mgIs49. Nanopore long-read sequencing shows that mgIs49 is a massive 8.8-Mb insertion - around 50% of the size of its host chromosome - which disrupts the prmt-9 gene. Both mgIs49 and another array, maIs105, cause dysregulation of the transcriptome and accumulation of reads mapping in sense-direction to transgene promoter sequences. We identify additional arrays exceeding 4 Mb and show that variable molting defects occur across different transgenic lines when combined with myrf-1(mg412), implicating array size or composition in the synthetic phenotype. Our results underscore the necessity of replacing multicopy reporters in developmental studies with single-copy insertions or endogenous tagging whenever possible.
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BibTeX
@article{katic2026large,
title = {{Large transgene arrays cause aberrant transcription and synthetic molting defects}},
author = {Iskra Katic and Panagiotis Papasaikas and Dimos Gaidatzis and Helge Großhans},
journal = {G3: Genes, Genomes, Genetics},
year = {2026},
month = oct,
doi = {10.1093/g3journal/jkag285},
url = {https://academic.oup.com/g3journal/advance-article/doi/10.1093/g3journal/jkag285/8869216},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Large transgene arrays cause aberrant transcription and synthetic molting defects
AU - Iskra Katic
AU - Panagiotis Papasaikas
AU - Dimos Gaidatzis
AU - Helge Großhans
PY - 2026
DA - 2026/10/06
JO - G3: Genes, Genomes, Genetics
DO - 10.1093/g3journal/jkag285
UR - https://academic.oup.com/g3journal/advance-article/doi/10.1093/g3journal/jkag285/8869216
AB - Multicopy transgene arrays remain widely used in Caenorhabditis elegans research. It is usually assumed that they behave neutrally, not impacting the phenotype under investigation. Here, we reveal that a previously reported heterochronic extra-molt phenotype associated with myrf-1(mg412) depends on the presence of the integrated molting reporter mgIs49. Nanopore long-read sequencing shows that mgIs49 is a massive 8.8-Mb insertion - around 50% of the size of its host chromosome - which disrupts the prmt-9 gene. Both mgIs49 and another array, maIs105, cause dysregulation of the transcriptome and accumulation of reads mapping in sense-direction to transgene promoter sequences. We identify additional arrays exceeding 4 Mb and show that variable molting defects occur across different transgenic lines when combined with myrf-1(mg412), implicating array size or composition in the synthetic phenotype. Our results underscore the necessity of replacing multicopy reporters in developmental studies with single-copy insertions or endogenous tagging whenever possible.
SN - 2160-1836
ER -