Yasmine Abbassi, Sara Cappelli, Eugenio Spagnolo, Alice Gennari, Giulia Visani, Simone Barattucci, Francesca Paron, Cristiana Stuani, Cristian A Droppelmann, Michael J Strong, Emanuele Buratti
{"title":"Axon guidance genes are regulated by TDP-43 and RGNEF through long-intron removal.","authors":"Yasmine Abbassi, Sara Cappelli, Eugenio Spagnolo, Alice Gennari, Giulia Visani, Simone Barattucci, Francesca Paron, Cristiana Stuani, Cristian A Droppelmann, Michael J Strong, Emanuele Buratti","doi":"10.1096/fj.202400743RR","DOIUrl":null,"url":null,"abstract":"<p><p>Rho guanine nucleotide exchange factor (RGNEF) is a guanine nucleotide exchange factor (GEF) mainly involved in regulating the activity of Rho-family GTPases. It is a bi-functional protein, acting both as a guanine exchange factor and as an RNA-binding protein. RGNEF is known to act as a destabilizing factor of neurofilament light chain RNA (NEFL) and it could potentially contribute to their sequestration in nuclear cytoplasmic inclusions. Most importantly, RGNEF inclusions in the spinal motor neurons of ALS patients have been shown to co-localize with inclusions of TDP-43, the major well-known RNA-binding protein aggregating in the brain and spinal cord of human patients. Therefore, it can be hypothesized that loss-of-function of both proteins following aggregation may contribute to motor neuron death/survival in ALS patients. To further characterize their relationship, we have compared the transcriptomic profiles of neuronal cells depleted of TDP-43 and RGNEF and show that these two factors predominantly act in an antagonistic manner when regulating the expression of axon guidance genes. From a mechanistic point of view, our experiments show that the effect of these genes on the processivity of long introns can explain their mode of action. Taken together, our results show that loss-of-function of factors co-aggregating with TDP-43 can potentially affect the expression of commonly regulated neuronal genes in a very significant manner, potentially acting as disease modifiers. This finding further highlights that neurodegenerative processes at the RNA level are the result of combinatorial interactions between different RNA-binding factors that can be co-aggregated in neuronal cells. A deeper understanding of these complex scenarios may lead to a better understanding of pathogenic mechanisms occurring in patients, where more than one specific protein may be aggregating in their neurons.</p>","PeriodicalId":50455,"journal":{"name":"FASEB Journal","volume":null,"pages":null},"PeriodicalIF":4.4000,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"FASEB Journal","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1096/fj.202400743RR","RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Rho guanine nucleotide exchange factor (RGNEF) is a guanine nucleotide exchange factor (GEF) mainly involved in regulating the activity of Rho-family GTPases. It is a bi-functional protein, acting both as a guanine exchange factor and as an RNA-binding protein. RGNEF is known to act as a destabilizing factor of neurofilament light chain RNA (NEFL) and it could potentially contribute to their sequestration in nuclear cytoplasmic inclusions. Most importantly, RGNEF inclusions in the spinal motor neurons of ALS patients have been shown to co-localize with inclusions of TDP-43, the major well-known RNA-binding protein aggregating in the brain and spinal cord of human patients. Therefore, it can be hypothesized that loss-of-function of both proteins following aggregation may contribute to motor neuron death/survival in ALS patients. To further characterize their relationship, we have compared the transcriptomic profiles of neuronal cells depleted of TDP-43 and RGNEF and show that these two factors predominantly act in an antagonistic manner when regulating the expression of axon guidance genes. From a mechanistic point of view, our experiments show that the effect of these genes on the processivity of long introns can explain their mode of action. Taken together, our results show that loss-of-function of factors co-aggregating with TDP-43 can potentially affect the expression of commonly regulated neuronal genes in a very significant manner, potentially acting as disease modifiers. This finding further highlights that neurodegenerative processes at the RNA level are the result of combinatorial interactions between different RNA-binding factors that can be co-aggregated in neuronal cells. A deeper understanding of these complex scenarios may lead to a better understanding of pathogenic mechanisms occurring in patients, where more than one specific protein may be aggregating in their neurons.
期刊介绍:
The FASEB Journal publishes international, transdisciplinary research covering all fields of biology at every level of organization: atomic, molecular, cell, tissue, organ, organismic and population. While the journal strives to include research that cuts across the biological sciences, it also considers submissions that lie within one field, but may have implications for other fields as well. The journal seeks to publish basic and translational research, but also welcomes reports of pre-clinical and early clinical research. In addition to research, review, and hypothesis submissions, The FASEB Journal also seeks perspectives, commentaries, book reviews, and similar content related to the life sciences in its Up Front section.