Bicc1 and dicer regulate left-right patterning through post-transcriptional control of the Nodal-inhibitor dand5
Markus Maerker, Maike Getwan, Megan E Dowdle, Jose L Pelliccia, Jason C McSheene, Valeria Yartseva, Katsura Minegishi, Philipp Vick, Antonio Giraldez, Hiroshi Hamada, Rebecca D Burdine, Michael D Sheets, Axel Schweickert, Martin Blum
Received Date: 13th January 20
Rotating cilia at the vertebrate left-right organizer (LRO) generate an asymmetric leftward flow, which is sensed by cells at the left LRO margin. How the flow signal is processed and relayed to the laterality-determining Nodal cascade in the left lateral plate mesoderm (LPM) is largely unknown. We previously showed that flow down-regulates mRNA expression of the Nodal inhibitor Dand5 in left sensory cells. De-repression of the co-expressed Nodal drives LPM Nodal cascade induction. Here, we identify the mechanism of dand5 downregulation, finding that its posttranscriptional repression is a central process in symmetry breaking. Specifically, the RNA binding protein Bicc1 interacts with a proximal element in the 3’-UTR of dand5 to repress translation in a dicer1-dependent manner. The bicc1/dicer1 module acts downstream of flow, as LRO ciliation was not affected upon its loss. Loss of bicc1 or dicer1 was rescued by parallel knockdown of dand5, placing both genes in the process of flow sensing.
Read in full at bioRxiv.
This is an abstract of a preprint hosted on an independent third party site. It has not been peer reviewed but is currently under consideration at Nature Communications.