Project description:ES cells express the miR-200 family which becomes down-regulated during the course of differentiation in serum. We generated an ES cell line which expresses miR-200c and miR-141 upon addition of doxycycline. Microarrays were used to gain a global picture of differentiation when miR-200c and miR-141 expression were maintained throughout differentiation through the addition of doxycycline.
Project description:Islet samples were sequenced to determine the effect of miR-200 KO or miR-200 site mutation in Zeb1 on tumorigenesis in RT2 mice; re-expression of individual miR-200 family members in miR-200KO cells was performed to determine the individual roles of miR-141 and miR-200c seeds
Project description:ES cells express the miR-200 family which becomes down-regulated during the course of differentiation in serum. We generated an ES cell line which expresses miR-200c and miR-141 upon addition of doxycycline. Microarrays were used to gain a global picture of differentiation when miR-200c and miR-141 expression were maintained throughout differentiation through the addition of doxycycline. A2.miR200c ES cells, which express miR-200c/miR-141 upon addition of doxycycline, were differentiated as embryoid bodies in six petri dishes. Half of the samples were treated with doxycycline on days 2 and 4 of differentiation, and RNA was collected from all samples on days 3, 4, and 5.
Project description:ERα is one of the most important transcription factors and therapeutic targets in breast cancer. The patterns of ERα expression in normal breast tissue and cancerous lesions are strikingly different. What drives the change of ERα pattern during lesions formation remains unclear. Here, we describe a novel regulatory mechanism through which miR-200c/141 regulates the level as well as the distribution of ERα in the mammary gland. miR-200c/141 is specifically expressed in luminal cells. Luminal-deletion of miR-200c/141 (miR-cKO) leads to a drastic expansion of ERα+ cell proportion. Single cell RNAseq reveals that miR-cKO generates aberrant luminal subpopulations with increased proliferative and anti-apoptotic features. In vivo lineage tracing of ER- luminal cells demonstrates that miR-200c/141 deletion can convert ER- cells into ER+ cells, which contribute partly to the increase of ERα+ luminal cells. Mechanistic study identifies Ccnd1 as a novel target of miR-200c/141 . Upon miR-200c/141deletion, elevated Ccnd1 level corroborates ERα transcriptional activation, leads to enhanced ERα signaling activity, consequently increased transcription of ERα coding gene Esr1 through self-activation at promoter E1. Our findings reveal a new miR-200c/141-Ccnd1-ERα axis, and provide new molecular insights into how miR-200c/141-Ccnd1 enforces the lineage barrier between ER- and ER+ luminal cells, and what drives the change of ERα expression pattern.
Project description:ERα is one of the most important transcription factors and therapeutic targets in breast cancer. The patterns of ERα expression in normal breast tissue and cancerous lesions are strikingly different. What drives the change of ERα pattern during lesions formation remains unclear. Here, we describe a novel regulatory mechanism through which miR-200c/141 regulates the level as well as the distribution of ERα in the mammary gland. miR-200c/141 is specifically expressed in luminal cells. Luminal-deletion of miR-200c/141 (miR-cKO) leads to a drastic expansion of ERα+ cell proportion. Single cell RNAseq reveals that miR-cKO generates aberrant luminal subpopulations with increased proliferative and anti-apoptotic features. In vivo lineage tracing of ER- luminal cells demonstrates that miR-200c/141 deletion can convert ER- cells into ER+ cells, which contribute partly to the increase of ERα+ luminal cells. Mechanistic study identifies Ccnd1 as a novel target of miR-200c/141 . Upon miR-200c/141deletion, elevated Ccnd1 level corroborates ERα transcriptional activation, leads to enhanced ERα signaling activity, consequently increased transcription of ERα coding gene Esr1 through self-activation at promoter E1. Our findings reveal a new miR-200c/141-Ccnd1-ERα axis, and provide new molecular insights into how miR-200c/141-Ccnd1 enforces the lineage barrier between ER- and ER+ luminal cells, and what drives the change of ERα expression pattern.
Project description:RNA sequencing of MDA-MB-231 cells expressing an empty vector (MDA-231EV), a vector containing the miR-200c/141 cluster (MDA-231c141) or a vector containing the miR-200b/200a/429 cluster
Project description:RNA sequencing of MDA-MB-231 cells expressing an empty vector (MDA-231EV), a vector containing the miR-200c/141 cluster (MDA-231c141) or a vector containing the miR-200b/200a/429 cluster
