Project description:The striatum is the main input structure of the basal ganglia, receiving information from the cortex and the thalamus and consisting of D1- and D2- medium spiny neurons (MSNs). D1-MSNs and D2-MSNs are essential for motor control and cognitive behaviors and have implications in Parkinson’s Disease. In the present study, we demonstrated that Sp9 positive progenitors produced both D1-MSNs and D2-MSNs and that Sp9 expression was rapidly downregulated in postmitotic D1-MSNs. Furthermore, we found that sustained Sp9 expression in lateral ganglionic eminence (LGE) progenitor cells and their descendants led to promoting D2-MSNs identity and repressing D1-MSNs identity during striatal development. As a result, sustained Sp9 expression resulted in an imbalance between D1-MSNs and D2-MSNs in the mouse striatum. In addition, the fate-changed D2 like-MSNs survived normally in adulthood. Taken together, our finding supported that Sp9 was sufficient to promote D2-MSNs identity and repress D1-MSNs identity, and Sp9 was a negative regulator of D1-MSNs fate. The striatum is the main input structure of the basal ganglia, receiving information from the cortex and the thalamus and consisting of D1- and D2- medium spiny neurons (MSNs). D1-MSNs and D2-MSNs are essential for motor control and cognitive behaviors and have implications in Parkinson’s Disease. In the present study, we demonstrated that Sp9 positive progenitors produced both D1-MSNs and D2-MSNs and that Sp9 expression was rapidly downregulated in postmitotic D1-MSNs. Furthermore, we found that sustained Sp9 expression in lateral ganglionic eminence (LGE) progenitor cells and their descendants led to promoting D2-MSNs identity and repressing D1-MSNs identity during striatal development. As a result, sustained Sp9 expression resulted in an imbalance between D1-MSNs and D2-MSNs in the mouse striatum. In addition, the fate-changed D2 like-MSNs survived normally in adulthood. Taken together, our finding supported that Sp9 was sufficient to promote D2-MSNs identity and repress D1-MSNs identity, and Sp9 was a negative regulator of D1-MSNs fate.
Project description:The striatum is the main input structure of the basal ganglia, receiving information from the cortex and the thalamus and consisting of D1- and D2- medium spiny neurons (MSNs). D1-MSNs and D2-MSNs are essential for motor control and cognitive behaviors and have implications in Parkinson’s Disease. In the present study, we demonstrated that Sp9 positive progenitors produced both D1-MSNs and D2-MSNs and that Sp9 expression was rapidly downregulated in postmitotic D1-MSNs. Furthermore, we found that sustained Sp9 expression in lateral ganglionic eminence (LGE) progenitor cells and their descendants led to promoting D2-MSNs identity and repressing D1-MSNs identity during striatal development. As a result, sustained Sp9 expression resulted in an imbalance between D1-MSNs and D2-MSNs in the mouse striatum. In addition, the fate-changed D2 like-MSNs survived normally in adulthood. Taken together, our finding supported that Sp9 was sufficient to promote D2-MSNs identity and repress D1-MSNs identity, and Sp9 was a negative regulator of D1-MSNs fate.
Project description:MicroRNA regulates protein expression of cells by repressing translation of specific target messenger transcripts. Loss of the neuron specific microRNA miR-128 in Dopamine D1-receptor expressing neurons in the murine striatum (D1-MSNs) lead to increased neuronal excitability, locomotor hyperactivity and fatal epilepsy. To examine expression changes in the absence of miR-128 in D1-MSNs, we used mice expressing EGFP-tagged ribosomes in D1-MSNs with either D1-MSN-specific homozygous deletion of miR-128-2 locus or no deletion. Transcripts co-immunoprecipitated with tagged ribosomes were analyzed by microarray. 9 mutant animals ( D1-MSN-tagged ribosome; D1-MSN specific miR-128-2 homozygous deletion) and 7 age matched littermate control animals (D1-MSN-tagged ribosome only).
Project description:The striatum is primarily composed of two types of medium spiny neurons (MSNs) expressing either D1- or D2-type dopamine receptors. However, the fate determination of these two types of neurons is not fully understood. Here, we found that D1 MSNs undergo fate switching to D2 MSNs in the absence of Zfp503. Furthermore, scRNA-seq revealed that the transcription factor Zfp503 affects the differentiation of these progenitor cells in the lateral ganglionic eminence (LGE). More importantly, we found that the transcription factors Sp8/9, which are required for the differentiation of D2 MSNs, are repressed by Zfp503.
Project description:MicroRNA regulates protein expression of cells by repressing translation of specific target messenger transcripts. Loss of the neuron specific microRNA miR-128 in Dopamine D1-receptor expressing neurons in the murine striatum (D1-MSNs) lead to increased neuronal excitability, locomotor hyperactivity and fatal epilepsy. To examine expression changes in the absence of miR-128 in D1-MSNs, we used mice expressing EGFP-tagged ribosomes in D1-MSNs with either D1-MSN-specific homozygous deletion of miR-128-2 locus or no deletion. Transcripts co-immunoprecipitated with tagged ribosomes were analyzed by microarray.
Project description:Cyclin D1-negative mantle cell lymphomas (MCL) are not well characterized, in part due to the difficulties in their recognition. SOX11 has been recently identified as a reliable biomarker of MCL, also expressed in the cyclin D1-negative variant. We investigated 40 lymphomas with MCL morphology and immunophenotype, negative for cyclin D1 expression/t(11;14)(q13;q32) but SOX11-positive. These tumors presented clinically with generalized lymphadenopathy, advanced stage, and had a poor outcome (5-year overall survival 48%). Chromosomal rearrangements of the CCND2 locus were detected in 55% of the cases, with an IG gene as partner in 18/22 cases, in particular with light chains (10 IGK@, 5 IGL@). No mutations in the phosphorylation motifs of CCND1, CCND2 and CCND3 were detected. The global genomic profile and the high complexity of the 32 cyclin D1-negative SOX11-positive MCL analyzed by copy number arrays were similar to the conventional cyclin D1/SOX11-positive MCL. 17p deletions and high Ki67 expression conferred a significantly worse outcome to the patients. This comprehensive characterization of a large series of cyclin D1-negative MCL indicates that these tumors are clinically and biologically similar to the conventional cyclin D1-positive MCL and provides a basis for the proper identification and clinical management of these patients.