# miR-200a Targets PITX2 to Mediate Goose Fibroblast Proliferation Through the Wnt Pathway

## TL;DR

This study explores how miR-200a regulates goose fibroblast proliferation via the Wnt pathway, offering insights into improving goose down quality.

## Contribution

The study identifies miR-200a's role in regulating goose fibroblast proliferation through PITX2 and the Wnt pathway, expanding the understanding of feather follicle development.

## Key findings

- miR-200a binds directly to PITX2’s 3′UTR, as shown by dual-luciferase reporter experiments.
- Overexpression of miR-200a suppresses GEDF proliferation and Wnt pathway gene expression.
- miR-200a's effect on GEDF proliferation depends on PITX2, as demonstrated by co-transfection experiments.

## Abstract

Goose down possesses significant economic value due to its exceptional softness and warmth properties. miRNAs have been demonstrated to indirectly influence feather follicle morphology, growth, and development through the targeted regulation of genes or pathways associated with hair/feather follicle formation. However, the current research on miRNAs in hair follicle (HF) development mainly focuses on the proliferation and differentiation of HF stem cells and the process of HF regeneration, and there are fewer studies on miRNAs in the process of early development of feather follicles, so it is worthy of in-depth research. Our findings reveal that miR-200a relies on PITX2 to mediate the Wnt pathway in order to regulate the proliferation of goose embryonic dermal fibroblasts (GEDFs) and thus may regulate goose feather follicle development. Collectively, this work expands the regulatory network underlying feather follicle development and provides a genetic foundation aimed at breeding geese with enhanced down production quality.

The economic value of goose down is attributed to its extensive application in the production of down-based clothing and related products. The primordium formation stage governs the proper morphogenesis of the feather follicle, while the Wnt signaling pathway serves a positive regulatory function during this stage. To identify critical miRNAs and molecular mechanisms regulating the development of goose feather follicle primordium, we performed transcriptomic sequencing of skin tissues collected from six geese at pre- and post-feather follicle primordium developmental stages. Bioinformatics analysis identified 350 differentially expressed miRNAs (DE miRNAs), which were functionally enriched in processes related to system development and multicellular organismal development, etc. As demonstrated by dual-luciferase reporter experiments, miR-200a binds directly to PITX2’s 3′ untranslated region (3′UTR). Furthermore, overexpression of miR-200a decreased the expression levels of genes linked to the Wnt pathway and suppressed the proliferation of GEDFs, as validated by RT-qPCR, CCK8, and EdU assays. Notably, co-transfection experiments demonstrated that miR-200a-mediated regulation of GEDF proliferation through the Wnt pathway is functionally dependent on PITX2. Collectively, this work expands the regulatory network underlying feather follicle development and provides a genetic foundation aimed at breeding geese with enhanced down production quality.