scholarly journals The conserved molting/circadian rhythm regulator NHR-23/NR1F1 serves as an essential co-regulator of C. elegans spermatogenesis

2020 ◽  
Author(s):  
James Matthew Ragle ◽  
Abigail L. Aita ◽  
Kayleigh N. Morrison ◽  
Raquel Martinez-Mendez ◽  
Hannah N. Saeger ◽  
...  
Keyword(s):  
Regulatory Networks ◽  
Nuclear Hormone Receptor ◽  
Model Systems ◽  
Residual Body ◽  
Major Sperm Protein ◽  
C Elegans ◽  
Summary Statement ◽  
Gene Regulatory ◽  
Established Role

AbstractIn sexually reproducing metazoans, spermatogenesis is the process by which uncommitted germ cells give rise to haploid sperm. Work in model systems has revealed mechanisms controlling commitment to the sperm fate, but how this fate is subsequently executed remains less clear. While studying the well-established role of the conserved nuclear hormone receptor transcription factor, NHR-23/NR1F1, in regulation of C. elegans molting, we discovered NHR-23/NR1F1 is also constitutively expressed in developing 1° spermatocytes and is a critical regulator of spermatogenesis. In this novel role, NHR-23/NR1F1 functions downstream of the canonical sex determination pathway. Degron-mediated depletion of NHR-23/NR1F1 within hermaphrodite or male germlines causes sterility due to an absence of functional sperm as depleted animals produce arrested primary spermatocytes rather than haploid sperm. These spermatocytes arrest in prometaphase I and fail to either progress to anaphase or attempt spermatid-residual body partitioning. They make sperm-specific membranous organelles (MOs) but fail to assemble their major sperm protein into fibrous bodies. NHR-23/NR1F1 appears to function independently of the known SPE-44 gene regulatory network, revealing the existence of an NHR-23/NR1F1-mediated module that regulates the spermatogenesis program.Summary StatementA well-characterized regulator of C. elegans molting also unexpectedly controls the spermatogenesis program; our work provides insights into the gene regulatory networks controlling spermatogenesis.

scholarly journals The conserved molting/circadian rhythm regulator NHR-23/NR1F1 serves as an essential co-regulator of C. elegans spermatogenesis

Development ◽  
2020 ◽  
Vol 147 (22) ◽  
pp. dev193862
Author(s):  
James Matthew Ragle ◽  
Abigail L. Aita ◽  
Kayleigh N. Morrison ◽  
Raquel Martinez-Mendez ◽  
Hannah N. Saeger ◽  
...  
Keyword(s):  
Regulatory Network ◽  
Nuclear Hormone Receptor ◽  
Model Systems ◽  
Residual Body ◽  
Major Sperm Protein ◽  
Sperm Protein ◽  
C Elegans ◽  
Gene Regulatory ◽  
Established Role

ABSTRACTIn sexually reproducing metazoans, spermatogenesis is the process by which uncommitted germ cells give rise to haploid sperm. Work in model systems has revealed mechanisms controlling commitment to the sperm fate, but how this fate is subsequently executed remains less clear. While studying the well-established role of the conserved nuclear hormone receptor transcription factor, NHR-23/NR1F1, in regulating C. elegans molting, we discovered that NHR-23/NR1F1 is also constitutively expressed in developing primary spermatocytes and is a critical regulator of spermatogenesis. In this novel role, NHR-23/NR1F1 functions downstream of the canonical sex-determination pathway. Degron-mediated depletion of NHR-23/NR1F1 within hermaphrodite or male germlines causes sterility due to an absence of functional sperm, as depleted animals produce arrested primary spermatocytes rather than haploid sperm. These spermatocytes arrest in prometaphase I and fail to either progress to anaphase or attempt spermatid-residual body partitioning. They make sperm-specific membranous organelles but fail to assemble their major sperm protein into fibrous bodies. NHR-23/NR1F1 appears to function independently of the known SPE-44 gene regulatory network, revealing the existence of an NHR-23/NR1F1-mediated module that regulates the spermatogenesis program.

How do histone modifications contribute to transgenerational epigenetic inheritance in C. elegans?

2020 ◽  
Vol 48 (3) ◽  
pp. 1019-1034 ◽  
Author(s):  
Rachel M. Woodhouse ◽  
Alyson Ashe
Keyword(s):  
Histone Modifications ◽  
Molecular Mechanisms ◽  
Epigenetic Inheritance ◽  
Nematode Caenorhabditis Elegans ◽  
Histone Methyltransferases ◽  
Transgenerational Epigenetic Inheritance ◽  
C Elegans ◽  
Recent Developments ◽  
Gene Regulatory

Gene regulatory information can be inherited between generations in a phenomenon termed transgenerational epigenetic inheritance (TEI). While examples of TEI in many animals accumulate, the nematode Caenorhabditis elegans has proven particularly useful in investigating the underlying molecular mechanisms of this phenomenon. In C. elegans and other animals, the modification of histone proteins has emerged as a potential carrier and effector of transgenerational epigenetic information. In this review, we explore the contribution of histone modifications to TEI in C. elegans. We describe the role of repressive histone marks, histone methyltransferases, and associated chromatin factors in heritable gene silencing, and discuss recent developments and unanswered questions in how these factors integrate with other known TEI mechanisms. We also review the transgenerational effects of the manipulation of histone modifications on germline health and longevity.

scholarly journals Extensive intraspecies cryptic variation in an ancient embryonic gene regulatory network

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Yamila N Torres Cleuren ◽  
Chee Kiang Ewe ◽  
Kyle C Chipman ◽  
Emily R Mears ◽  
Cricket G Wood ◽  
...  
Keyword(s):  
Gene Regulatory Networks ◽  
Regulatory Networks ◽  
Recombinant Inbred Lines ◽  
Single Species ◽  
C Elegans ◽  
Cryptic Variation ◽  
Absolute Requirement ◽  
Natural Isolates ◽  
Gene Regulatory ◽  
Metazoan Phylogeny

Innovations in metazoan development arise from evolutionary modification of gene regulatory networks (GRNs). We report widespread cryptic variation in the requirement for two key regulatory inputs, SKN-1/Nrf2 and MOM-2/Wnt, into the C. elegans endoderm GRN. While some natural isolates show a nearly absolute requirement for these two regulators, in others, most embryos differentiate endoderm in their absence. GWAS and analysis of recombinant inbred lines reveal multiple genetic regions underlying this broad phenotypic variation. We observe a reciprocal trend, in which genomic variants, or knockdown of endoderm regulatory genes, that result in a high SKN-1 requirement often show low MOM-2/Wnt requirement and vice-versa, suggesting that cryptic variation in the endoderm GRN may be tuned by opposing requirements for these two key regulatory inputs. These findings reveal that while the downstream components in the endoderm GRN are common across metazoan phylogeny, initiating regulatory inputs are remarkably plastic even within a single species.

scholarly journals Evolution of gene regulatory networks by means of selection and random genetic drift

2018 ◽  
Author(s):  
Antonios Kioukis ◽  
Pavlos Pavlidis
Keyword(s):  
Natural Selection ◽  
Positive Selection ◽  
Genetic Drift ◽  
Regulatory Networks ◽  
Fitness Landscape ◽  
Random Genetic Drift ◽  
Maturation Period ◽  
Evolutionary Forces ◽  
Gene Regulatory

The evolution of a population by means of genetic drift and natural selection operating on a gene regulatory network (GRN) of an individual has not been scrutinized in depth. Thus, the relative importance of various evolutionary forces and processes on shaping genetic variability in GRNs is understudied. Furthermore, it is not known if existing tools that identify recent and strong positive selection from genomic sequences, in simple models of evolution, can detect recent positive selection when it operates on GRNs. Here, we propose a simulation framework, called EvoNET, that simulates forward-in-time the evolution of GRNs in a population. Since the population size is finite, random genetic drift is explicitly applied. The fitness of a mutation is not constant, but we evaluate the fitness of each individual by measuring its genetic distance from an optimal genotype. Mutations and recombination may take place from generation to generation, modifying the genotypic composition of the population. Each individual goes through a maturation period, where its GRN reaches equilibrium. At the next step, individuals compete to produce the next generation. As time progresses, the beneficial genotypes push the population higher in the fitness landscape. We examine properties of the GRN evolution such as robustness against the deleterious effect of mutations and the role of genetic drift. We confirm classical results from Andreas Wagner’s work that GRNs show robustness against mutations and we provide new results regarding the interplay between random genetic drift and natural selection.

scholarly journals Integration of Metabolic and Gene Regulatory Networks Modulates the C. elegans Dietary Response

Cell ◽  
2013 ◽  
Vol 153 (6) ◽  
pp. 1406-1407
Author(s):  
Emma Watson ◽  
Lesley T. MacNeil ◽  
H. Efsun Arda ◽  
Lihua Julie Zhu ◽  
Albertha J.M. Walhout
Keyword(s):  
Gene Regulatory Networks ◽  
Regulatory Networks ◽  
C Elegans ◽  
Gene Regulatory

scholarly journals Identification of cancer biomarkers of prognostic value using specific gene regulatory networks (GRN): a novel role of RAD51AP1 for ovarian and lung cancers

2017 ◽  
Vol 39 (3) ◽  
pp. 407-417 ◽  
Author(s):  
Dimple Chudasama ◽  
Valeria Bo ◽  
Marcia Hall ◽  
Vladimir Anikin ◽  
Jeyarooban Jeyaneethi ◽  
...  
Keyword(s):  
Gene Regulatory Networks ◽  
Prognostic Value ◽  
Regulatory Networks ◽  
Cancer Biomarkers ◽  
Specific Gene ◽  
Lung Cancers ◽  
Gene Regulatory

scholarly journals Emergent properties of HNF4α-PPARγ network may drive consequent phenotypic plasticity in NAFLD

2020 ◽  
Author(s):  
Sarthak Sahoo ◽  
Divyoj Singh ◽  
Priyanka Chakraborty ◽  
Mohit Kumar Jolly
Keyword(s):  
Liver Disease ◽  
Phenotypic Plasticity ◽  
Regulatory Networks ◽  
Emergent Properties ◽  
Alcoholic Fatty Liver ◽  
Global Presence ◽  
Adults And Children ◽  
Gene Regulatory ◽  
Emergent Dynamics

ABSTRACTNon-Alcoholic Fatty Liver Disease (NAFLD) is the most common form of chronic liver disease in adults and children. It is characterized by excessive accumulation of lipids in the hepatocytes of patients without any excess alcohol intake. With a global presence of 24% and limited therapeutic options, the disease burden of NAFLD is increasing. Thus, it becomes imperative to attempt to understand the dynamics of disease progression at a systems-level. Here, we decode the emergent dynamics of underlying gene regulatory networks that have been identified to drive the initiation and progression of NAFLD. We have developed a mathematical model to elucidate the dynamics of the HNF4α-PPARγ gene regulatory network. Our simulations reveal that this network can enable multiple co-existing phenotypes under certain biological conditions: an adipocyte, a hepatocyte, and a “hybrid” adipocyte-like state of the hepatocyte. These phenotypes may also switch among each other, thus enabling phenotypic plasticity and consequently leading to simultaneous deregulation of the levels of molecules that maintain a hepatic identity and/or facilitate a partial or complete acquisition of adipocytic traits. These predicted trends are supported by the analysis of clinical data, further substantiating the putative role of phenotypic plasticity in driving NAFLD. Our results unravel how the emergent dynamics of underlying regulatory networks can promote phenotypic plasticity, thereby propelling the clinically observed changes in gene expression often associated with NAFLD.

scholarly journals The Contribution of Autophagy and LncRNAs to MYC-Driven Gene Regulatory Networks in Cancers

2021 ◽  
Vol 22 (16) ◽  
pp. 8527
Author(s):  
Leila Jahangiri ◽  
Perla Pucci ◽  
Tala Ishola ◽  
Ricky M. Trigg ◽  
John A. Williams ◽  
...  
Keyword(s):  
Gene Networks ◽  
Regulatory Networks ◽  
Metabolic Reprogramming ◽  
Cellular Processes ◽  
Cancer Genomes ◽  
Mutual Regulation ◽  
Myc Gene ◽  
Gene Regulatory ◽  
Non Coding Rnas

MYC is a target of the Wnt signalling pathway and governs numerous cellular and developmental programmes hijacked in cancers. The amplification of MYC is a frequently occurring genetic alteration in cancer genomes, and this transcription factor is implicated in metabolic reprogramming, cell death, and angiogenesis in cancers. In this review, we analyse MYC gene networks in solid cancers. We investigate the interaction of MYC with long non-coding RNAs (lncRNAs). Furthermore, we investigate the role of MYC regulatory networks in inducing changes to cellular processes, including autophagy and mitophagy. Finally, we review the interaction and mutual regulation between MYC and lncRNAs, and autophagic processes and analyse these networks as unexplored areas of targeting and manipulation for therapeutic gain in MYC-driven malignancies.

Sign in / Sign up

Export Citation Format

Share Document