scholarly journals 509 A Glycine-rich Protein from Tomato Involved in Pollen Wall Formation

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 533C-533
Author(s):  
Alan G. Smith ◽  
Kenneth J. McNeil
Keyword(s):  
Pollen Development ◽  
Polyclonal Antibodies ◽  
Outer Wall ◽  
Protein Levels ◽  
Isolation And Characterization ◽  
Sporophytic Tissue ◽  
Mother Cells ◽  
Transgenic Tomatoes ◽  
And Function ◽  
Glycine Rich Protein

The sporophytic tissue of the anther and, in particular, the tapetum, a cell layer surrounding the pollen sac, is know to be essential for the production of pollen. The isolation and characterization of the gene 92B from tomato that encodes an extracellular glycine rich protein (GRP) has been used to further elucidate the role of the tapetum in pollen development. RNA from the 92B gene accumulates exclusively in the tapetum. Polyclonal antibodies raised against the 92B GRP detect four proteins in stamens with microspores beginning meiosis. In pollen extracts, the antibodies detect a single protein. Expression of the tomato 92B gene in transgenic tobacco indicates that the four protein products are derived from only the 92B gene. The 92B GRP is localized to the tapetum, the callose wall of microspore mother cells, the exine (outer wall) of mature pollen, and orbicules. Orbicules are globular bodies derived from tapetal material that form on the tapetum wall and line the exterior of the pollen sac. Expression of 92B antisense RNA resulted in a significant decrease of 92B RNA and protein levels in transgenic tomatoes. This reduction was correlated with a decrease in pollen germination and an abnormal exine morphology. The function of the 92B protein in pollen development and function will be discussed.

scholarly journals Extracellular vesicles as mediators and markers of acute organ injury: current concepts

2021 ◽  
Author(s):  
Birte Weber ◽  
Niklas Franz ◽  
Ingo Marzi ◽  
Dirk Henrich ◽  
Liudmila Leppik
Keyword(s):  
Extracellular Vesicles ◽  
Inflammatory Diseases ◽  
Organ Injury ◽  
Isolation And Characterization ◽  
Communication Processes ◽  
Incidence And Mortality ◽  
New Biomarkers ◽  
And Function

AbstractDue to the continued high incidence and mortality rate worldwide, there is a need to develop new strategies for the quick, precise, and valuable recognition of presenting injury pattern in traumatized and poly-traumatized patients. Extracellular vesicles (EVs) have been shown to facilitate intercellular communication processes between cells in close proximity as well as distant cells in healthy and disease organisms. miRNAs and proteins transferred by EVs play biological roles in maintaining normal organ structure and function under physiological conditions. In pathological conditions, EVs change the miRNAs and protein cargo composition, mediating or suppressing the injury consequences. Therefore, incorporating EVs with their unique protein and miRNAs signature into the list of promising new biomarkers is a logical next step. In this review, we discuss the general characteristics and technical aspects of EVs isolation and characterization. We discuss results of recent in vitro, in vivo, and patients study describing the role of EVs in different inflammatory diseases and traumatic organ injuries. miRNAs and protein signature of EVs found in patients with acute organ injury are also debated.

scholarly journals Restoration of Noradrenergic Function in Parkinson’s Disease Model Mice

ASN NEURO ◽  
2021 ◽  
Vol 13 ◽  
pp. 175909142110097
Author(s):  
Kui Cui ◽  
Fan Yang ◽  
Turan Tufan ◽  
Muhammad U. Raza ◽  
Yanqiang Zhan ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Transcription Factors ◽  
Disease Model ◽  
Neuronal Loss ◽  
Mrna Levels ◽  
Gene Therapies ◽  
Protein Levels ◽  
Dopaminergic Systems ◽  
And Function

Dysfunction of the central noradrenergic and dopaminergic systems is the primary neurobiological characteristic of Parkinson’s disease (PD). Importantly, neuronal loss in the locus coeruleus (LC) that occurs in early stages of PD may accelerate progressive loss of dopaminergic neurons. Therefore, restoring the activity and function of the deficient noradrenergic system may be an important therapeutic strategy for early PD. In the present study, the lentiviral constructions of transcription factors Phox2a/2b, Hand2 and Gata3, either alone or in combination, were microinjected into the LC region of the PD model VMAT2 Lo mice at 12 and 18 month age. Biochemical analysis showed that microinjection of lentiviral expression cassettes into the LC significantly increased mRNA levels of Phox2a, and Phox2b, which were accompanied by parallel increases of mRNA and proteins of dopamine β-hydroxylase (DBH) and tyrosine hydroxylase (TH) in the LC. Furthermore, there was considerable enhancement of DBH protein levels in the frontal cortex and hippocampus, as well as enhanced TH protein levels in the striatum and substantia nigra. Moreover, these manipulations profoundly increased norepinephrine and dopamine concentrations in the striatum, which was followed by a remarkable improvement of the spatial memory and locomotor behavior. These results reveal that over-expression of these transcription factors in the LC improves noradrenergic and dopaminergic activities and functions in this rodent model of PD. It provides the necessary groundwork for the development of gene therapies of PD, and expands our understanding of the link between the LC-norepinephrine and dopamine systems during the progression of PD.

scholarly journals Genetic Relationships in the Toxin-Producing Fungal Endophyte, Alternaria oxytropis Using Polyketide Synthase and Non-Ribosomal Peptide Synthase Genes

2021 ◽  
Vol 7 (7) ◽  
pp. 538
Author(s):  
Rebecca Creamer ◽  
Deana Baucom Hille ◽  
Marwa Neyaz ◽  
Tesneem Nusayr ◽  
Christopher L. Schardl ◽  
...  
Keyword(s):  
Amino Acid ◽  
Polyketide Synthase ◽  
Genetic Relationships ◽  
Protein Sequences ◽  
Fungal Endophyte ◽  
Melanin Synthesis ◽  
Melanin Biosynthesis ◽  
Protein Levels ◽  
Oxytropis Sericea ◽  
And Function

The legume Oxytropis sericea hosts a fungal endophyte, Alternaria oxytropis, which produces secondary metabolites (SM), including the toxin swainsonine. Polyketide synthase (PKS) and non-ribosomal peptide synthase (NRPS) enzymes are associated with biosynthesis of fungal SM. To better understand the origins of the SM, an unannotated genome of A. oxytropis was assessed for protein sequences similar to known PKS and NRPS enzymes of fungi. Contigs exhibiting identity with known genes were analyzed at nucleotide and protein levels using available databases. Software were used to identify PKS and NRPS domains and predict identity and function. Confirmation of sequence for selected gene sequences was accomplished using PCR. Thirteen PKS, 5 NRPS, and 4 PKS-NRPS hybrids were identified and characterized with functions including swainsonine and melanin biosynthesis. Phylogenetic relationships among closest amino acid matches with Alternaria spp. were identified for seven highly conserved PKS and NRPS, including melanin synthesis. Three PKS and NRPS were most closely related to other fungi within the Pleosporaceae family, while five PKS and PKS-NRPS were closely related to fungi in the Pleosporales order. However, seven PKS and PKS-NRPS showed no identity with fungi in the Pleosporales or the class Dothideomycetes, suggesting a different evolutionary origin for those genes.

scholarly journals DBC1 (Deleted in Breast Cancer 1) modulates the stability and function of the nuclear receptor Rev-erbα

2013 ◽  
Vol 451 (3) ◽  
pp. 453-461 ◽  
Author(s):  
Claudia C. S. Chini ◽  
Carlos Escande ◽  
Veronica Nin ◽  
Eduardo N. Chini
Keyword(s):  
Breast Cancer ◽  
Nuclear Receptor ◽  
Clock Genes ◽  
Mrna Levels ◽  
Protein Levels ◽  
The Stability ◽  
And Function ◽  
Interfering Rna ◽  
In Cells

The nuclear receptor Rev-erbα has been implicated as a major regulator of the circadian clock and integrates circadian rhythm and metabolism. Rev-erbα controls circadian oscillations of several clock genes and Rev-erbα protein degradation is important for maintenance of the circadian oscillations and also for adipocyte differentiation. Elucidating the mechanisms that regulate Rev-erbα stability is essential for our understanding of these processes. In the present paper, we report that the protein DBC1 (Deleted in Breast Cancer 1) is a novel regulator of Rev-erbα. Rev-erbα and DBC1 interact in cells and in vivo, and DBC1 modulates the Rev-erbα repressor function. Depletion of DBC1 by siRNA (small interfering RNA) in cells or in DBC1-KO (knockout) mice produced a marked decrease in Rev-erbα protein levels, but not in mRNA levels. In contrast, DBC1 overexpression significantly enhanced Rev-erbα protein stability by preventing its ubiquitination and degradation. The regulation of Rev-erbα protein levels and function by DBC1 depends on both the N-terminal and C-terminal domains of DBC1. More importantly, in cells depleted of DBC1, there was a dramatic decrease in circadian oscillations of both Rev-erbα and BMAL1. In summary, our data identify DBC1 as an important regulator of the circadian receptor Rev-erbα and proposes that Rev-erbα could be involved in mediating some of the physiological effects of DBC1.

scholarly journals A disease-associated frameshift mutation in caveolin-1 disrupts caveolae formation and function through introduction of a de novo ER retention signal

2017 ◽  
Vol 28 (22) ◽  
pp. 3095-3111 ◽  
Author(s):  
Courtney A. Copeland ◽  
Bing Han ◽  
Ajit Tiwari ◽  
Eric D. Austin ◽  
James E. Loyd ◽  
...  
Keyword(s):  
Frameshift Mutation ◽  
De Novo ◽  
Dominant Negative ◽  
Caveolin 1 ◽  
Protein Levels ◽  
C Terminus ◽  
Er Retention ◽  
And Function ◽  
Er Retention Signal ◽  
Retention Signal

Caveolin-1 (CAV1) is an essential component of caveolae and is implicated in numerous physiological processes. Recent studies have identified heterozygous mutations in the CAV1 gene in patients with pulmonary arterial hypertension (PAH), but the mechanisms by which these mutations impact caveolae assembly and contribute to disease remain unclear. To address this question, we examined the consequences of a familial PAH-associated frameshift mutation in CAV1, P158PfsX22, on caveolae assembly and function. We show that C-terminus of the CAV1 P158 protein contains a functional ER-retention signal that inhibits ER exit and caveolae formation and accelerates CAV1 turnover in Cav1–/– MEFs. Moreover, when coexpressed with wild-type (WT) CAV1 in Cav1–/– MEFs, CAV1-P158 functions as a dominant negative by partially disrupting WT CAV1 trafficking. In patient skin fibroblasts, CAV1 and caveolar accessory protein levels are reduced, fewer caveolae are observed, and CAV1 complexes exhibit biochemical abnormalities. Patient fibroblasts also exhibit decreased resistance to a hypo-osmotic challenge, suggesting the function of caveolae as membrane reservoir is compromised. We conclude that the P158PfsX22 frameshift introduces a gain of function that gives rise to a dominant negative form of CAV1, defining a new mechanism by which disease-associated mutations in CAV1 impair caveolae assembly.

Functional and molecular characterization of NHE3 expression during ontogeny in rat jejunal epithelium

1997 ◽  
Vol 273 (6) ◽  
pp. C1937-C1946 ◽  
Author(s):  
James F. Collins ◽  
Hua Xu ◽  
Pawel R. Kiela ◽  
Jiamin Zeng ◽  
Fayez K. Ghishan
Keyword(s):  
Northern Blot ◽  
Polyclonal Antibodies ◽  
Membrane Vesicle ◽  
Age Groups ◽  
Fold Increase ◽  
Jejunal Mucosa ◽  
Mrna Levels ◽  
Adult Rats ◽  
Intestinal Brush Border Membrane ◽  
Protein Levels

Ontogenic changes occur in intestinal brush-border membrane vesicle (BBMV) Na+/H+exchange activity. The present studies were designed to investigate ontogenic changes in Na+/H+exchanger (NHE) isoform 3 in rat jejunum. pH-dependent Na+ uptake was assayed in four age groups of rats in the presence of 0, 50, or 800 μM HOE-694, a specific NHE inhibitor with differential sensitivities for NHE2 [inhibition constant ( K i) = 5 μM in PS120 fibroblasts] and NHE3 ( K i = 650 μM). Results showed that NHE2 and NHE3 contribute to basal BBMV uptake at all ages. Uptake levels were highest in 6-wk-old rats, lower in adult rats, and lowest in 2-wk-old (suckling) and 3-wk-old (weanling) rats. NHE3 contribution ranged from 92% at 6 wk of age to 59% at 2 and 3 wk of age. NHE3 inhibition by 800 μM HOE-694 was 38–45%. Statistical analysis showed that HOE-694 had a significant effect at both concentrations at all ages and that differences were present between all ages except 2- and 3-wk rats (at all HOE-694 concentrations). Northern blot analyses of jejunal mucosa showed lowest NHE3 mRNA levels in 2-wk animals and higher levels in all other age groups. Polyclonal antibodies were developed against an NHE3 COOH-terminal fusion protein, and antiserum was characterized with NHE3-transfected PS120 cells and by immunohistochemistry. Western blot analyses showed lowest protein levels in 2-wk animals and higher levels in the other ages. Suckling rats were subcutaneously injected with methylprednisone (MP) for 2 days and killed 1 day later. Northern blot analyses showed a twofold increase in NHE3 mRNA expression with MP treatment. Immunoblot analyses showed a 2.5-fold increase in NHE3 immunoreactive protein levels with MP injection. Overall, these data suggest that NHE3 is regulated during ontogeny and that ontogenic changes are most apparent around the time of weaning. Furthermore, the data suggest that NHE3 is regulated at transcriptional and posttranscriptional levels during mammalian intestinal development.

GAMYB TF modulates bHLH142 and is homeostatically regulated by TDR TF during rice anther tapetal and pollen development

2021 ◽  
Author(s):  
Swee-Suak Ko ◽  
Min-Jeng Li ◽  
Yi-Cheng Ho ◽  
Chun-Ping Yu ◽  
Ting-Ting Yang ◽  
...  
Keyword(s):  
Pollen Development ◽  
Molecular Mechanisms ◽  
Early Stage ◽  
Specific Binding ◽  
Biological Functions ◽  
Altered Expression ◽  
Regulatory Pathways ◽  
E Box ◽  
And Function ◽  
Different Tissues

Abstract GAMYB, UDT1, TIP2/bHLH142, TDR, and EAT1/DTD are important transcription factors (TFs) that play a crucial role during rice pollen development. This study demonstrates that bHLH142 acts downstream of UDT1 and GAMYB and works as a “hub” in these two pollen pathways. We show that GAMYB modulates bHLH142 expression through specific binding to the MYB motif of bHLH142 promoter during early stage of pollen development; while TDR acts as a transcriptional repressor of the GAMYB modulation of bHLH142 by binding to the E-box close to the MYB motif on the promoter. The altered expression of TFs highlights the importance that a tight, precise, and coordinated regulation among these TFs is essential for normal pollen development. Most notably, this study illustrates the regulatory pathways of GAMYB and UDT1 that rely on bHLH142 in a direct and an indirect manner, respectively, and function in different tissues with distinct biological functions during pollen development. This study advances our understanding of the molecular mechanisms of rice pollen development.

TETRASPORE is required for male meiotic cytokinesis in Arabidopsis thaliana

Development ◽  
1997 ◽  
Vol 124 (13) ◽  
pp. 2645-2657 ◽  
Author(s):  
M. Spielman ◽  
D. Preuss ◽  
F.L. Li ◽  
W.E. Browne ◽  
R.J. Scott ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Pollen Development ◽  
Male Meiosis ◽  
Pollen Grain ◽  
Flowering Plants ◽  
External Wall ◽  
Normal Pollen ◽  
Wide Range ◽  
Asymmetric Divisions ◽  
And Function

In flowering plants, male meiosis occurs in the microsporocyte to produce four microspores, each of which develops into a pollen grain. Here we describe four mutant alleles of TETRASPORE (TES), a gene essential for microsporocyte cytokinesis in Arabidopsis thaliana. Following failure of male meiotic cytokinesis in tes mutants, all four microspore nuclei remain within the same cytoplasm, with some completing their developmental programmes to form functional pollen nuclei. Both of the mitotic divisions seen in normal pollen development take place in tes mutants, including the asymmetric division required for the differentiation of gametes; some tes grains perform multiple asymmetric divisions in the same cytoplasm. tes pollen shows a variety of abnormalities subsequent to the cytokinetic defect, including fusion of nuclei, formation of ectopic internal walls, and disruptions to external wall patterning. In addition, ovules fertilized by tes pollen often abort, possibly because of excess paternal genomes in the endosperm. Thus tes mutants not only reveal a gene specific to male meiosis, but aid investigation of a wide range of processes in pollen development and function.

XMAP230 is required for the assembly and organization of acetylated microtubules and spindles in Xenopus oocytes and eggs

1998 ◽  
Vol 111 (16) ◽  
pp. 2315-2327 ◽  
Author(s):  
B.J. Cha ◽  
B. Error ◽  
D.L. Gard
Keyword(s):  
Late Stage ◽  
Xenopus Oocytes ◽  
Early Stage ◽  
Polyclonal Antibodies ◽  
Stage Iv ◽  
Stage I ◽  
Meiotic Spindle ◽  
Heat Stable ◽  
Early Embryos ◽  
And Function

We used affinity-purified polyclonal antibodies to characterize the distribution and function of XMAP230, a heat-stable microtubule-associated protein isolated from Xenopus eggs, during oogenesis. Immunoblots revealed that XMAP230 was present throughout oogenesis and early development, but was most abundant in late stage oocytes, eggs, and early embryos. Immunofluorescence microscopy revealed that XMAP230 was associated with microtubules in oogonia, post-mitotic stage 0 oocytes, early stage I oocytes, and during stage IV-VI of oogenesis. However, staining of microtubules by anti-XMAP230 was not detectable during late stage I through stage III. In stage VI oocytes, anti-XMAP230 stained a large subset of microtubules that were also stained with monoclonal antibodies specific for acetylated (α)-tubulin. During oocyte maturation, XMAP230 was associated with the transient microtubule array that serves as the precursor of the first meiotic spindle, as well as both first and second meiotic spindles. The extensive array of cytoplasmic microtubules present throughout maturation was not detectably stained by anti-XMAP230. Microinjection of anti-XMAP230 locally disrupted the organization and acetylation of microtubules in stage VI oocytes, and reduced the re-acetylation of microtubules during recovery from cold-induced microtubule disassembly. Subsequent maturation of oocytes injected with anti-XMAP230 resulted in defects in the assembly of the transient microtubules array and first meiotic spindle. These observations suggest that XMAP230 is required for the stabilization and organization of cytoplasmic and spindle microtubules in Xenopus oocytes and eggs.

FKBP51 Modulates Hippocampal Size and Function in Post-translational Regulation of Parkin

2021 ◽  
Author(s):  
Bin Qiu ◽  
Zhaohui Zhong ◽  
Shawn Righter ◽  
Yuxue Xu ◽  
Jun Wang ◽  
...  
Keyword(s):  
Hippocampal Neurons ◽  
Translational Regulation ◽  
Disease Onset ◽  
Fold Increase ◽  
Knock Out ◽  
Fk506 Binding Protein ◽  
Protein Levels ◽  
And Function

Abstract FK506-binding protein 51 (encoded by Fkpb51) has been associated with stress-related mental illness. To identify its function, we studied the morphological consequences of Fkbp51 deletion. Artificial Intelligence-assist morphological analysis identified that Fkbp51 knock-out (KO) mice possess more elongated CA and DG but shorter in height in coronal section when compared to WT. Primary cultured Fkbp51 KO hippocampal neurons were shown to exhibit larger dendritic outgrowth than wild-type (WT) controls, pharmacological manipulation experiments suggest that this may occur through regulation of microtubule-associated protein. Both in vitro primary culture and in vivo labeling support that FKBP51 regulates microtubule-associated protein expression. Furthermore, in the absence of differences in mRNA expression, Fkbp51 KO hippocampus exhibited decreases in βIII-tubulin, MAP2, and Tau protein levels, but a greater than 2.5-fold increase in Parkin protein. Overexpression and knock-down FKBP51 demonstrated that FKBP51 negatively regulates Parkin in a dose-dependent and ubiquitin-mediated manner. These results indicate a potential novel post-translational regulatory of Parkin by FKBP51 and significance of their interaction on disease onset.

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