Giovanni Stefani

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MicroRNAs play important roles in animal development, cell differentiation, and metabolism and have been implicated in human cancer. The let-7 microRNA controls the timing of cell cycle exit and terminal differentiation in Caenorhabditis elegans and is poorly expressed or deleted in human lung tumors. Here, we show that let-7 is highly expressed in normal(More)
Fragile-X mental retardation is caused by loss of function of a single gene encoding the Fragile-X mental retardation protein, FMRP, an RNA-binding protein that harbors two KH-type and one RGG-type RNA-binding domains. Previous studies identified intramolecular G-quartet RNAs as high-affinity targets for the RGG box, but the relationship of RNA binding to(More)
The modulation of gene expression by small non-coding RNAs is a recently discovered level of gene regulation in animals and plants. In particular, microRNAs (miRNAs) and Piwi-interacting RNAs (piRNAs) have been implicated in various aspects of animal development, such as neuronal, muscle and germline development. During the past year, an improved(More)
Nova proteins are a neuron-specific alternative splicing factors. We have combined bioinformatics, biochemistry and genetics to derive an RNA map describing the rules by which Nova proteins regulate alternative splicing. This map revealed that the position of Nova binding sites (YCAY clusters) in a pre-messenger RNA determines the outcome of splicing. The(More)
We have combined genetic and biochemical approaches to analyze the function of the RNA-binding protein Nova-1, the paraneoplastic opsoclonus-myoclonus ataxia (POMA) antigen. Nova-1 null mice die postnatally from a motor deficit associated with apoptotic death of spinal and brainstem neurons. Nova-1 null mice show specific splicing defects in two inhibitory(More)
The Nova paraneoplastic antigens are neuron-specific RNA binding proteins that participate in the control of alternative splicing. We have used the yeast two-hybrid system to isolate Nova interacting proteins and identify an RNA binding protein that is closely related to the polypyrimidine tract-binding protein (PTB). The expression of this protein, brPTB,(More)
Fragile X mental retardation protein (FMRP) is an RNA binding protein encoded by the gene FMR1, whose expression is impaired in patients with fragile X mental retardation. The association of FMRP with polyribosomes in non-neural cell lines has previously suggested that FMRP is involved in translational regulation. However, the relevance of these studies to(More)
In the nematode Caenorhabditis elegans, the let-7 microRNA (miRNA) controls the timing of key developmental events and terminal differentiation in part by directly regulating lin-41. C. elegans lin-41 mutants display precocious cell cycle exit and terminal differentiation of epidermal skin cells. lin-41 orthologues are found in more complex organisms(More)
The Nova family of neuron-specific RNA-binding proteins were originally identified as targets in an autoimmune neurologic disease characterized by failure of motor inhibition. Nova-1 regulates alternative splicing of pre-mRNAs encoding the inhibitory neurotransmitter receptor subunits GABA(A)Rgamma2 and GlyRalpha2 by directly binding intronic elements,(More)
The evolutionarily conserved gene lin-28 encodes an RNA-binding protein and is an important regulator of the proper temporal succession of several developmental events in both invertebrates and vertebrates. At the cellular level, LIN-28 promotes stemness and proliferation, and inhibits differentiation, a feature best illustrated by its ability to induce(More)