Alternative splicing regulates stochastic NLRP3 activity

Leucine-rich repeat (LRR) domains are evolutionarily conserved in proteins that function in development and immunity. Here we report strict exonic modularity of LRR domains of several human gene families, which is a precondition for alternative splicing (AS). We provide evidence for AS of LRR domain within several Nod-like receptors, most prominently the inflammasome sensor NLRP3. Human NLRP3, but not mouse NLRP3, is expressed as two major isoforms, the full-length variant and a variant lacking exon 5. Moreover, NLRP3 AS is stochastically regulated, with NLRP3. exon 5 lacking the interaction surface for NEK7 and hence loss of activity. Our data thus reveals unexpected regulatory roles of AS through differential utilization of LRRs modules in vertebrate innate immunity

Molecular regulation of mRNA stability and translation

The flow of information from DNA to RNA to protein is a tightly regulated process, which ultimately determines the functional properties that each cell will possess. Defects in any of the multiple regulatory mechanisms that ensure that proper amounts of each protein are produced within a particular cell, may lead to dysregulation of cellular processes and disease. This dissertation will deal with 2 different projects. The common theme between these projects is that we studied post-transcriptional regulation of gene expression at the level of messenger RNA (mRNA), and in both studies we took advantage of genome-wide sequencing techniques to develop insights and novel hypothesis within the realm of neurobiology. Briefly, the first project is a study of the role of Cyfip1, a neuropsychiatric disease risk gene, in regulating the translation of its mRNA partners. We show that deletion and over-expression of Cyfip1 in the mouse brain, leads to diametric changes in protein translation of NMDAR subunits and postsynaptic components, and has consequences in behavior within these mouse models. The second study is an exploration of the role of m6A epitranscriptional modification in the regulation of cortical neurogenesis in-vivo, where we identified a critical and conserved role of m6A in the temporal control of mammalian cortical neurogenesis

Algorithmen zum Entschlüsseln der Genregulation

Die Hochdurchsatz-Sequenzierung erzeugt riesige Mengen fragmentierter genetischer Daten. Unser Labor verwendet fortschrittliche Algorithmen, um diese Informationen wieder zusammenzusetzen und versteckte Muster zu erkennen. Höhere Organismen speichern ihr genetisches Material als Desoxyribonukleinsäure (DNA) in den Zellkernen. In einem Prozess namens Transkription werden einzelne Abschnitte, die Gene, in Boten Ribonukleinsäuren (mRNAs) umgewandelt. Anschließend entstehen durch den Translationsprozess Proteine als wichtigste Funktionseinheiten

Alternative splicing regulates stochastic NLRP3 activity

Leucine-rich repeat (LRR) domains are evolutionarily conserved in proteins that function in development and immunity. Here we report strict exonic modularity of LRR domains of several human gene families, which is a precondition for alternative splicing (AS). We provide evidence for AS of LRR domain within several Nod-like receptors, most prominently the inflammasome sensor NLRP3. Human NLRP3, but not mouse NLRP3, is expressed as two major isoforms, the full-length variant and a variant lacking exon 5. Moreover, NLRP3 AS is stochastically regulated, with NLRP3 exon 5 lacking the interaction surface for NEK7 and hence loss of activity. Our data thus reveals unexpected regulatory roles of AS through differential utilization of LRRs modules in vertebrate innate immunity

Alternative splicing regulates stochastic NLRP3 activity.

Leucine-rich repeat (LRR) domains are evolutionarily conserved in proteins that function in development and immunity. Here we report strict exonic modularity of LRR domains of several human gene families, which is a precondition for alternative splicing (AS). We provide evidence for AS of LRR domain within several Nod-like receptors, most prominently the inflammasome sensor NLRP3. Human NLRP3, but not mouse NLRP3, is expressed as two major isoforms, the full-length variant and a variant lacking exon 5. Moreover, NLRP3 AS is stochastically regulated, with NLRP3 ∆ exon 5 lacking the interaction surface for NEK7 and hence loss of activity. Our data thus reveals unexpected regulatory roles of AS through differential utilization of LRRs modules in vertebrate innate immunity

FAM111A mutations result in hypoparathyroidism and impaired skeletal development

Kenny-Caffey syndrome (KCS) and the similar but more severe osteocraniostenosis (OCS) are genetic conditions characterized by impaired skeletal development with small and dense bones, short stature, and primary hypoparathyroidism with hypocalcemia. We studied five individuals with KCS and five with OCS and found that all of them had heterozygous mutations in FAM111A. One mutation was identified in four unrelated individuals with KCS, and another one was identified in two unrelated individuals with OCS; all occurred de novo. Thus, OCS and KCS are allelic disorders of different severity. FAM111A codes for a 611 amino acid protein with homology to trypsin-like peptidases. Although FAM111A has been found to bind to the large T-antigen of SV40 and restrict viral replication, its native function is unknown. Molecular modeling of FAM111A shows that residues affected by KCS and OCS mutations do not map close to the active site but are clustered on a segment of the protein and are at, or close to, its outer surface, suggesting that the pathogenesis involves the interaction with as yet unidentified partner proteins rather than impaired catalysis. FAM111A appears to be crucial to a pathway that governs parathyroid hormone production, calcium homeostasis, and skeletal development and growth. © 2013 The American Society of Human Genetics

FAM111A Mutations Result in Hypoparathyroidism and Impaired Skeletal Development.

Kenny-Caffey syndrome (KCS) and the similar but more severe osteocraniostenosis (OCS) are genetic conditions characterized by impaired skeletal development with small and dense bones, short stature, and primary hypoparathyroidism with hypocalcemia. We studied five individuals with KCS and five with OCS and found that all of them had heterozygous mutations in FAM111A. One mutation was identified in four unrelated individuals with KCS, and another one was identified in two unrelated individuals with OCS; all occurred de novo. Thus, OCS and KCS are allelic disorders of different severity. FAM111A codes for a 611 amino acid protein with homology to trypsin-like peptidases. Although FAM111A has been found to bind to the large T-antigen of SV40 and restrict viral replication, its native function is unknown. Molecular modeling of FAM111A shows that residues affected by KCS and OCS mutations do not map close to the active site but are clustered on a segment of the protein and are at, or close to, its outer surface, suggesting that the pathogenesis involves the interaction with as yet unidentified partner proteins rather than impaired catalysis. FAM111A appears to be crucial to a pathway that governs parathyroid hormone production, calcium homeostasis, and skeletal development and growth