pha-4 is Ce-fkh-1, a fork head/HNF-3alpha, beta, gamma homolog that functions in organogenesis of the C. elegans pharynx

Development ◽  
1998 ◽  
Vol 125 (12) ◽  
pp. 2171-2180 ◽  
Author(s):  
J.M. Kalb ◽  
K.K. Lau ◽  
B. Goszczynski ◽  
T. Fukushige ◽  
D. Moons ◽  
...  

The C. elegans Ce-fkh-1 gene has been cloned on the basis of its sequence similarity to the winged-helix DNA binding domain of the Drosophila fork head and mammalian HNF-3alpha, beta, gamma genes, and mutations in the zygotically active pha-4 gene have been shown to block formation of the pharynx (and rectum) at an early stage in embryogenesis. In the present paper, we show that Ce-fkh-1 and pha-4 are the same gene. We show that PHA-4 protein is present in nuclei of essentially all pharyngeal cells, of all five cell types. PHA-4 protein first appears close to the point at which a cell lineage will produce only pharyngeal cells, independently of cell type. We show that PHA-4 binds directly to a ‘pan-pharyngeal enhancer element’ previously identified in the promoter of the pharyngeal myosin myo-2 gene; in transgenic embryos, ectopic PHA-4 activates ectopic myo-2 expression. We also show that ectopic PHA-4 can activate ectopic expression of the ceh-22 gene, a pharyngeal-specific NK-2-type homeodomain protein previously shown to bind a muscle-specific enhancer near the PHA-4 binding site in the myo-2 promoter. We propose that it is the combination of pha-4 and regulatory molecules such as ceh-22 that produces the specific gene expression patterns during pharynx development. Overall, pha-4 can be described as an ‘organ identity factor’, completely necessary for organ formation, present in all cells of the organ from the earliest stages, capable of integrating upstream developmental pathways (in this case, the two distinct pathways that produce the anterior and posterior pharynx) and participating directly in the transcriptional regulation of organ specific genes. Finally, we note that the distribution of PHA-4 protein in C. elegans embryos is remarkably similar to the distribution of the fork head protein in Drosophila embryos: high levels in the foregut/pharynx and hindgut/rectum; low levels in the gut proper. Moreover, we show that pha-4 expression in the C. elegans gut is regulated by elt-2, a C. elegans gut-specific GATA-factor and possible homolog of the Drosophila gene serpent, which influences fork head expression in the fly gut. Overall, our results provide evidence for a highly conserved pathway regulating formation of the digestive tract in all (triploblastic) metazoa.

2000 ◽  
Vol 15 (1) ◽  
pp. 26-32 ◽  
Author(s):  
M. Cattaneo ◽  
R. Orlandi ◽  
C. Ronchini ◽  
P. Granelli ◽  
G. Malferrari ◽  
...  

We have previously reported on the isolation and chromosomal mapping of a novel human gene (SEL1L), which shows sequence similarity to sel-1, an extragenic suppressor of C. elegans. sel-1 functions as a negative regulator of lin-12 activity, the latter being implicated in the control of diverse cellular differentiation events. In the present study we compare the expression patterns of SEL1L and TAN-1, the human ortholog of lin-12 in normal and neoplastic cells. We found that, whereas both genes are expressed in fetal tissues at similar levels, they are differentially expressed in normal adult and neoplastic cells. In normal adult cells SEL1L is generally present at very low levels; only in the cells of the pancreas does it show maximum expression. By contrast, SEL1L is generally well represented in most neoplastic cells but not in those of pancreatic and gastric carcinomas, where transcription is either downregulated or completely repressed. TAN-1 on the other hand is well represented in almost all normal and neoplastic cells, with very few exceptions. Our observations suggest that SEL1L is presumably implicated in pancreatic and gastric carcinogenesis and that, along with TAN-1, it is very important for normal cell function. Alterations in the expression of SEL1L may be used as a prognostic marker for gastric and pancreatic cancers.


2005 ◽  
Vol 17 (6) ◽  
pp. 625 ◽  
Author(s):  
Xiang-Shun Cui ◽  
Hyuk Song ◽  
Nam-Hyung Kim

Annealing control primer (ACP)-based GeneFishing polymerase chain reaction (PCR) was used to identify the genes that are specifically or prominently expressed in porcine oocytes at the metaphase II (MII) and germinal vesicle (GV) stages. By using 60 ACPs, 13 differentially expressed genes (DEGs) were identified. The cloned genes or expressed sequence tags (ESTs) showed sequence similarity with known genes or ESTs of other species in GenBank. The mRNA expression during oocyte maturation and early embryonic development in both pigs and mice of four of these genes (namely transcription factor TZP, annexin A2, hypoxia-inducible protein 2, and ATPase 6) was further characterised by real-time quantitative reverse transcription–PCR. All four genes were markedly upregulated in pig and mouse MII oocytes compared with GV-stage oocytes. The expression levels of the four genes decreased gradually during early cleavage. Thus, these genes may play important roles during oocyte maturation and/or early cleavage in mammals. Although the detailed functions of these genes remain to be determined, their identification in the present study provides insights into meiotic maturation and fertilisation.


2021 ◽  
Vol 15 ◽  
Author(s):  
Rasoul Godini ◽  
Ava Handley ◽  
Roger Pocock

Behavior encompasses the physical and chemical response to external and internal stimuli. Neurons, each with their own specific molecular identities, act in concert to perceive and relay these stimuli to drive behavior. Generating behavioral responses requires neurons that have the correct morphological, synaptic, and molecular identities. Transcription factors drive the specific gene expression patterns that define these identities, controlling almost every phenomenon in a cell from development to homeostasis. Therefore, transcription factors play an important role in generating and regulating behavior. Here, we describe the transcription factors, the pathways they regulate, and the neurons that drive chemosensation, mechanosensation, thermosensation, osmolarity sensing, complex, and sex-specific behaviors in the animal model Caenorhabditis elegans. We also discuss the current limitations in our knowledge, particularly our minimal understanding of how transcription factors contribute to the adaptive behavioral responses that are necessary for organismal survival.


Author(s):  
Jacques Serizay ◽  
Yan Dong ◽  
Jürgen Jänes ◽  
Michael Chesney ◽  
Chiara Cerrato ◽  
...  

AbstractDespite increasingly detailed knowledge of gene expression patterns, the regulatory architectures that drive them are not well understood. To address this, we compared transcriptional and regulatory element activities across five adult tissues of C. elegans, covering ∼90% of cells, and defined regulatory grammars associated with ubiquitous, germline and somatic tissue-specific gene expression patterns. We find architectural features that distinguish two major promoter types. Germline-specific and ubiquitously-active promoters have well positioned +1 and −1 nucleosomes associated with a periodic 10-bp WW signal. Somatic tissue-specific promoters lack these features, have wider nucleosome depleted regions, and are more enriched for core promoter elements, which surprisingly differ between tissues. A 10-bp periodic WW signal is also associated with +1 nucleosomes of ubiquitous promoters in fly and zebrafish but is not detected in mouse and human. Our results demonstrate fundamental differences in regulatory architectures of germline-active and somatic tissue-specific genes and provide a key resource for future studies.


Development ◽  
2002 ◽  
Vol 129 (4) ◽  
pp. 853-862 ◽  
Author(s):  
Behrooz Esmaeili ◽  
Jennifer M. Ross ◽  
Cara Neades ◽  
David M. Miller ◽  
Julie Ahringer

Locomotory activity is defined by the specification of motoneurone subtypes. In the nematode, C. elegans, DA and DB motoneurones innervate dorsal muscles and function to induce movement in the backwards or forwards direction, respectively. These two neurone classes express separate sets of genes and extend axons with oppositely directed trajectories; anterior (DA) versus posterior (DB). The DA-specific homeoprotein UNC-4 interacts with UNC-37/Groucho to repress the DB gene, acr-5 (nicotinic acetylcholine receptor subunit). We show that the C. elegans even-skipped-like homoedomain protein, VAB-7, coordinately regulates different aspects of the DB motoneurone fate, in part by repressing unc-4. Wild-type DB motoneurones express VAB-7, have posteriorly directed axons, express ACR-5 and lack expression of the homeodomain protein UNC-4. In a vab-7 mutant, ectopic UNC-4 represses acr-5 and induces an anteriorly directed DB axon trajectory. Thus, vab-7 indirectly promotes DB-specific gene expression and posteriorly directed axon outgrowth by preventing UNC-4 repression of DB differentiation. Ectopic expression of VAB-7 also induces DB traits in an unc-4-independent manner, suggesting that VAB-7 can act through a parallel pathway. This work supports a model in which a complementary pair of homeodomain transcription factors (VAB-7 and UNC-4) specifies differences between DA and DB neurones through inhibition of the alternative fates. The recent findings that Even-skipped transcriptional repressor activity specifies neurone identity and axon guidance in the mouse and Drosophila motoneurone circuit points to an ancient origin for homeoprotein-dependent mechanisms of neuronal differentiation in the metazoan nerve cord.


2021 ◽  
Author(s):  
Debamalya Chatterjee ◽  
Kameron Wittmeyer ◽  
Tzuu-fen Lee ◽  
Jin Cui ◽  
Neela H Yennawar ◽  
...  

Abstract Maize (Zea mays L.) Ufo1-1 is a spontaneous dominant mutation of the unstable factor for orange1 (ufo1). We recently cloned ufo1, which is a Poaceae specific gene expressed solely during seed development in maize. Here we have characterized Ufo1-1 and a loss-of-function Ds insertion allele (ufo1-Dsg) to decipher the role of ufo1 in maize. We found that both ufo1 mutant alleles impact sugars and hormones, and have defects in the basal endosperm transfer layer (BETL) and adjacent cell types. The Ufo1-1 BETL had reduced cell elongation and cell wall ingrowth, resulting in cuboidal shaped transfer cells. In contrast, the ufo1-Dsg BETL cells showed a reduced overall size with abnormal wall ingrowth. Expression analysis identified the impact of ufo1 on several genes essential for BETL development. The overexpression of Ufo1-1 in various tissues leads to ectopic phenotypes, including abnormal cell organization and stomata subsidiary cell defects. Interestingly, pericarp and leaf transcriptomes also showed that as compared to wild type, Ufo1-1 had ectopic expression of endosperm development-specific genes. This study shows that Ufo1-1 impacts the expression patterns of a wide range of genes involved in various developmental processes.


2008 ◽  
Vol 205 (3) ◽  
pp. 611-624 ◽  
Author(s):  
Alan B. Cantor ◽  
Hiromi Iwasaki ◽  
Yojiro Arinobu ◽  
Tyler B. Moran ◽  
Hirokazu Shigematsu ◽  
...  

The zinc finger transcription factor GATA-1 requires direct physical interaction with the cofactor friend of GATA-1 (FOG-1) for its essential role in erythroid and megakaryocytic development. We show that in the mast cell lineage, GATA-1 functions completely independent of FOG proteins. Moreover, we demonstrate that FOG-1 antagonizes the fate choice of multipotential progenitor cells for the mast cell lineage, and that its down-regulation is a prerequisite for mast cell development. Remarkably, ectopic expression of FOG-1 in committed mast cell progenitors redirects them into the erythroid, megakaryocytic, and granulocytic lineages. These lineage switches correlate with transcriptional down-regulation of GATA-2, an essential mast cell GATA factor, via switching of GATA-1 for GATA-2 at a key enhancer element upstream of the GATA-2 gene. These findings illustrate combinatorial control of cell fate identity by a transcription factor and its cofactor, and highlight the role of transcriptional networks in lineage determination. They also provide evidence for lineage instability during early stages of hematopoietic lineage commitment.


2018 ◽  
Author(s):  
Annabel Ebbing ◽  
Abel Vertesy ◽  
Marco Betist ◽  
Bastiaan Spanjaard ◽  
Jan Philipp Junker ◽  
...  

SummaryTo advance our understanding of the genetic programs that drive cell and tissue specialization, it is necessary to obtain a comprehensive overview of gene expression patterns. Here, we have used RNA tomography to generate the first high-resolution, anteroposterior gene expression maps of C. elegans males and hermaphrodites. To explore these maps, we have developed computational methods for discovering region and tissue-specific genes. Moreover, by combining pattern-based analysis with differential gene expression analysis, we have found extensive sex-specific gene expression differences in the germline and sperm. We have also identified genes that are specifically expressed in the male reproductive tract, including a group of uncharacterized genes that encode small secreted proteins that are required for male fertility. We conclude that spatial gene expression maps provide a powerful resource for identifying novel tissue-specific gene functions in C. elegans. Importantly, we found that expression maps from different animals can be precisely aligned, which opens up new possibilities for transcriptome-wide comparisons of gene expression patterns.


2021 ◽  
pp. 002203452110120
Author(s):  
C. Gluck ◽  
S. Min ◽  
A. Oyelakin ◽  
M. Che ◽  
E. Horeth ◽  
...  

The parotid, submandibular, and sublingual glands represent a trio of oral secretory glands whose primary function is to produce saliva, facilitate digestion of food, provide protection against microbes, and maintain oral health. While recent studies have begun to shed light on the global gene expression patterns and profiles of salivary glands, particularly those of mice, relatively little is known about the location and identity of transcriptional control elements. Here we have established the epigenomic landscape of the mouse submandibular salivary gland (SMG) by performing chromatin immunoprecipitation sequencing experiments for 4 key histone marks. Our analysis of the comprehensive SMG data sets and comparisons with those from other adult organs have identified critical enhancers and super-enhancers of the mouse SMG. By further integrating these findings with complementary RNA-sequencing based gene expression data, we have unearthed a number of molecular regulators such as members of the Fox family of transcription factors that are enriched and likely to be functionally relevant for SMG biology. Overall, our studies provide a powerful atlas of cis-regulatory elements that can be leveraged for better understanding the transcriptional control mechanisms of the mouse SMG, discovery of novel genetic switches, and modulating tissue-specific gene expression in a targeted fashion.


Genetics ◽  
2000 ◽  
Vol 155 (2) ◽  
pp. 721-731 ◽  
Author(s):  
Teresa D Shippy ◽  
Jianhua Guo ◽  
Susan J Brown ◽  
Richard W Beeman ◽  
Robin E Denell

Abstract The Tribolium castaneum homeotic gene maxillopedia (mxp) is the ortholog of Drosophila proboscipedia (pb). Here we describe and classify available mxp alleles. Larvae lacking all mxp function die soon after hatching, exhibiting strong transformations of maxillary and labial palps to legs. Hypomorphic mxp alleles produce less severe transformations to leg. RNA interference with maxillopedia double-stranded RNA results in phenocopies of mxp mutant phenotypes ranging from partial to complete transformations. A number of gain-of-function (GOF) mxp alleles have been isolated based on transformations of adult antennae and/or legs toward palps. Finally, we have characterized the mxp expression pattern in wild-type and mutant embryos. In normal embryos, mxp is expressed in the maxillary and labial segments, whereas ectopic expression is observed in some GOF variants. Although mxp and Pb display very similar expression patterns, pb null embryos develop normally. The mxp mutant larval phenotype in Tribolium is consistent with the hypothesis that an ancestral pb-like gene had an embryonic function that was lost in the lineage leading to Drosophila.


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