scholarly journals Phenotypical Characterization of a Mutant dea1 With Developmental Defect in Female Inflorescence and Mutantion Impact on Yield in Maize

2022 ◽  
Vol 14 (2) ◽  
pp. 1
Author(s):  
Fei Zheng ◽  
Meijing Zhang ◽  
Yiwen Zhen ◽  
Jianhua Yuan ◽  
Wenming Zhao ◽  
...  
Keyword(s):  
Maize Yield ◽  
High Yield ◽  
Regulation Mechanism ◽  
Developmental Defect ◽  
Wild Type ◽  
Phenotypic Analysis ◽  
Adaxial Side ◽  
Inflorescence Morphology ◽  
Female Inflorescence ◽  
Agronomical Traits

The establishment of female inflorescence morphology is of great significance to the formation of final maize yield. defective ear1 (dea1) is a novel maize mutant with developmental defect of female inflorescence caused by natural variation. Morphological analysis revealed that the mutant dea1 was characterized as a “scar-like” crack on the adaxial side of the top of the ear, accounting for 28.6-100.0% of the ear length, with an average of 32.4%. The results of scanning electron microscope showed that there was collapse in the formation of paired spikelet primordium at the base of the axillary meristem. Most of investigated botanical and agronomical traits of dea1 were lower than those of wild type, except for ear length and hundred grain weight. The grain yield per ear of mutant dea1 was 35.93% lower than that of wild type, and the width of mutation crack contributed the most to the yield loss per ear. The identification of the mutant dea1 and the characteristically phenotypic analysis provide a theoretical basis for the study of the molecular regulation mechanism of ear development and the application of high-yield breeding in maize.The establishment of female inflorescence morphology is of great significance to the formation of final maize yield. defective ear1 (dea1) is a novel maize mutant with developmental defect of female inflorescence caused by natural variation. Morphological analysis revealed that the mutant dea1 was characterized as a “scar-like” crack on the adaxial side of the top of the ear, accounting for 28.6-100.0% of the ear length, with an average of 32.4%. The results of scanning electron microscope showed that there was collapse in the formation of paired spikelet primordium at the base of the axillary meristem. Most of investigated botanical and agronomical traits of dea1 were lower than those of wild type, except for ear length and hundred grain weight. The grain yield per ear of mutant dea1 was 35.93% lower than that of wild type, and the width of mutation crack contributed the most to the yield loss per ear. The identification of the mutant dea1 and the characteristically phenotypic analysis provide a theoretical basis for the study of the molecular regulation mechanism of ear development and the application of high-yield breeding in maize.

scholarly journals A Genetic Method for Generating Drosophila Eyes Composed Exclusively of Mitotic Clones of a Single Genotype

Genetics ◽  
1999 ◽  
Vol 152 (4) ◽  
pp. 1631-1639 ◽  
Author(s):  
R Steven Stowers ◽  
Thomas L Schwarz
Keyword(s):  
Developmental Stage ◽  
Genetic Screens ◽  
Wild Type ◽  
Phenotypic Analysis ◽  
Standard Methods ◽  
Genetic Method ◽  
Lethal Mutations ◽  
Single Genotype ◽  
Late Developmental Stage ◽  
Fly Eye

Abstract The genetic analysis of a gene at a late developmental stage can be impeded if the gene is required at an earlier developmental stage. The construction of mosaic animals, particularly in Drosophila, has been a means to overcome this obstacle. However, the phenotypic analysis of mitotic clones is often complicated because standard methods for generating mitotic clones render mosaic tissues that are a composite of both mutant and phenotypically normal cells. We describe here a genetic method (called EGUF/hid) that uses both the GAL4/UAS and FLP/FRT systems to overcome this limitation for the Drosophila eye by producing genetically mosaic flies that are otherwise heterozygous but in which the eye is composed exclusively of cells homozygous for one of the five major chromosome arms. These eyes are nearly wild type in size, morphology, and physiology. Applications of this genetic method include phenotypic analysis of existing mutations and F1 genetic screens to identify as yet unknown genes involved in the biology of the fly eye. We illustrate the utility of the method by applying it to lethal mutations in the synaptic transmission genes synaptotagmin and syntaxin.

scholarly journals A Novel and Efficient High-Yield Method for Preparing Bacterial Ghosts

Toxins ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 420
Author(s):  
Yi Ma ◽  
Liu Cui ◽  
Meng Wang ◽  
Qiuli Sun ◽  
Kaisheng Liu ◽  
...  
Keyword(s):  
Large Scale ◽  
Expression System ◽  
High Yield ◽  
Wild Type ◽  
High Quality ◽  
Efficient Protection ◽  
Bacterial Ghosts ◽  
Cell Envelopes ◽  
Extracellular Structures ◽  
First Time

Bacterial ghosts (BGs) are empty cell envelopes possessing native extracellular structures without a cytoplasm and genetic materials. BGs are proposed to have significant prospects in biomedical research as vaccines or delivery carriers. The applications of BGs are often limited by inefficient bacterial lysis and a low yield. To solve these problems, we compared the lysis efficiency of the wild-type protein E (EW) from phage ΦX174 and the screened mutant protein E (EM) in the Escherichia coli BL21(DE3) strain. The results show that the lysis efficiency mediated by protein EM was improved. The implementation of the pLysS plasmid allowed nearly 100% lysis efficiency, with a high initial cell density as high as OD600 = 2.0, which was higher compared to the commonly used BG preparation method. The results of Western blot analysis and immunofluorescence indicate that the expression level of protein EM was significantly higher than that of the non-pLysS plasmid. High-quality BGs were observed by SEM and TEM. To verify the applicability of this method in other bacteria, the T7 RNA polymerase expression system was successfully constructed in Salmonella enterica (S. Enterica, SE). A pET vector containing EM and pLysS were introduced to obtain high-quality SE ghosts which could provide efficient protection for humans and animals. This paper describes a novel and commonly used method to produce high-quality BGs on a large scale for the first time.

scholarly journals GAGA Factor Isoforms Have Distinct but Overlapping Functions In Vivo

2001 ◽  
Vol 21 (24) ◽  
pp. 8565-8574 ◽  
Author(s):  
Anthony J. Greenberg ◽  
Paul Schedl
Keyword(s):  
Fusion Protein ◽  
Transcriptional Activation ◽  
Functional Difference ◽  
Wild Type ◽  
Gaga Factor ◽  
Phenotypic Analysis ◽  
Alternatively Spliced

ABSTRACT The Drosophila melanogaster GAGA factor (encoded by the Trithorax-like [Trl] gene) is required for correct chromatin architecture at diverse chromosomal sites. The Trl gene encodes two alternatively spliced isoforms of the GAGA factor (GAGA-519 and GAGA-581) that are identical except for the length and sequence of the C-terminal glutamine-rich (Q) domain. In vitro and tissue culture experiments failed to find any functional difference between the two isoforms. We made a set of transgenes that constitutively express cDNAs coding for either of the isoforms with the goal of elucidating their roles in vivo. Phenotypic analysis of the transgenes in Trl mutant background led us to the conclusion that GAGA-519 and GAGA-581 perform different, albeit largely overlapping, functions. We also expressed a fusion protein with LacZ disrupting the Q domain of GAGA-519. This LacZ fusion protein compensated for the loss of wild-type GAGA factor to a surprisingly large extent. This suggests that the Q domain either is not required for the essential functions performed by the GAGA protein or is exclusively used for tetramer formation. These results are inconsistent with a major role of the Q domain in chromatin remodeling or transcriptional activation. We also found that GAGA-LacZ was able to associate with sites not normally occupied by the GAGA factor, pointing to a role of the Q domain in binding site choice in vivo.

16. Physiological effects of IDH1 loss-of-function on Chondrocyte Differentiation through Hedgehog Pathway upregulation

2018 ◽  
Author(s):  
Cassie Tyson
Keyword(s):  
Developmental Stages ◽  
Hedgehog Pathway ◽  
Chondrocyte Differentiation ◽  
Loss Of Function ◽  
Wild Type ◽  
Phenotypic Analysis ◽  
Growth Plate Chondrocytes ◽  
Idh Mutations ◽  
Cartilage Tumors ◽  
Deficient Mice

Cartilage tumors are the most common and terminal primary neoplasms in bone. Physiologically, bones formed through endochondral ossification are regulated by the Hedgehog pathway and Parathyroid hormone-like hormone feedback loop. The upregulation of the infamous Hedgehog pathway has been demonstrated in several non-cartilaginous neoplasms. Recently, frequent mutational events of isocitrate dehydrogenase1 (IDH1) were identified in cartilage tumors. In other neoplasms, IDH mutations produces an oncometabolite that can promote HIF1a activation, contributing to tumorigenesis. Currently, the role of IDH1 mutations in cartilage tumors remain unknown. Investigating the physiological aspect of IDH1proves useful in identifying novel therapeutic targets for cartilage tumors. IDH1 deficient and wild-type littermates, were harvested for forelimbs and hindlimbs at various developmental stages for phenotypic analysis via hematoxylin and eosin staining. Histological analysis demonstrated IDH1 homozygous deficient mice at embryonic stages exhibited dwarfism and an elongated layer of hypertrophic chondrocytes. This was verified via immunohistochemistry Type 10 Collagen staining and Quantitative PCR (qPCR) using the chondrocyte terminal differentiation marker Col10a1. Whole skeletons of IDH1 deficient mice were subjected to skeletal double staining which demonstrated delayed mineralization of underdeveloped IDH1 deficient mice contrasted with wild-type littermates. qPCR was performed to examine the status of chondrocyte differentiation through the Hedgehog pathway in cultured primarymouse growth plate chondrocytes. Interestingly, IDH1 deficient non-neoplastic cells revealed significant upregulation of Hedgehog target molecules in IDH1 deficient chondrocytes. As a result, the loss-offunction of IDH1 was identified as a potential impairment of chondrocyte differentiation and a factor towards chondrocyte tumorgenisis.

A myb-related protein required for culmination in Dictyostelium

Development ◽  
1999 ◽  
Vol 126 (12) ◽  
pp. 2813-2822 ◽  
Author(s):  
K. Guo ◽  
C. Anjard ◽  
A. Harwood ◽  
H.J. Kim ◽  
P.C. Newell ◽  
...  
Keyword(s):  
Developmental Defect ◽  
Intercellular Signaling ◽  
Wild Type ◽  
Fruiting Body Formation ◽  
Dependent Protein Kinase ◽  
Myb Gene ◽  
Repeat Domain ◽  
Intercellular Signalling ◽  
Dependent Protein ◽  
Signaling Process

The avian retroviral v-myb gene and its cellular homologues throughout the animal and plant kingdoms contain a conserved DNA binding domain. We have isolated an insertional mutant of Dictyostelium unable to switch from slug migration to fruiting body formation i.e. unable to culminate. The gene that is disrupted, mybC, codes for a protein with a myb-like domain that is recognized by an antibody against the v-myb repeat domain. During development of myb+ cells, mybC is expressed only in prestalk cells. When developed together with wild-type cells mybC- cells are able to form both spores and stalk cells very efficiently. Their developmental defect is also bypassed by overexpressing cAMP-dependent protein kinase. However even when their defect is bypassed, mybC null slugs and culminates produce little if any of the intercellular signalling peptides SDF-1 and SDF-2 that are believed to be released by prestalk cells at culmination. We propose that the mybC gene product is required for an intercellular signaling process controlling maturation of stalk cells and spores and that SDF-1 and/or SDF-2 may be implicated in this process.

scholarly journals Mechanism of PQQ and CoQ10 overproduction in Methylobacterium as revealed by comparative genomic analysis between mutant and wild-type strains

2020 ◽  
Author(s):  
Changle Zhao ◽  
Yinping Wan ◽  
Xiaojie Cao ◽  
Huili Zhang ◽  
Xin Bao
Keyword(s):  
Mutant Strain ◽  
Type Strain ◽  
Wild Type Strain ◽  
Genomic Analysis ◽  
Comparative Genomic Analysis ◽  
Comparative Genomic ◽  
Regulation Mechanism ◽  
Whole Genome ◽  
Wild Type ◽  
Coq10 Production

Abstract Background The microbial synthesis of pyrroloquinoline quinone (PQQ) and Coenzyme Q10 (CoQ10) remains the most promising industrial production route. Methylobacterium has been used to generate PQQ and other value-added chemicals from cheap carbon feedstocks.However, the low PQQ and CoQ10 production capacity of the Methylobacterium strains is a major limitation The regulation mechanism for PQQ and CoQ10 biosynthesis in this strain has also not been fully elucidated. Results Methylobacterium sp. CLZ strain was isolated from soil contaminated with chemical wastewater, which can simultaneously produce PQQ, CoQ10, and carotenoids by using cheap methanol as carbon source. We investigated a mutant strain NI91, which increased the PQQ and CoQ10 yield by 72.44% and 59.80%, respectively. Whole-genome sequencing of NI91 and wild-type strain CLZ revealed that both contain a 5.28 Mb chromosome. The comparative genomic analysis and validation study revealed that a significant increase in biomass and PQQ production was associated with the base mutations in the methanol dehydrogenase (MDH) synthesis genes, mxaD and mxaJ. The significant increase in CoQ10 production may be associated with the base mutations in dxs gene, a key gene in the MEP/DOXP pathway. Conclusions A PQQ producing strain that simultaneously produces CoQ10 and carotenoids was selected and after ANI analysis, named as Methylobacterium sp. CLZ. After random mutagenesis of this strain, we obtained NI91 strain, which showed increased production of PQQ and CoQ10. Based on comparative genomic analysis of the whole genome of mutant strain NI91 and wild-type strain CLZ, a total of 270 SNPs and InDels events were detected, which provided a reference for subsequent research. The mutations in mxaD, mxaJ and dxs genes may be related to the high yield of PQQ and CoQ10. These findings will enhance our understanding of the PQQ and CoQ10 over-production mechanism in Methylobacterium sp. NI91 at the genomic level. It will also provide useful clues for strain engineering in order to improve the PQQ and CoQ10 production.

scholarly journals Genome Size: A Novel Predictor of Nut Weight and Nut Size of Walnut Trees

HortScience ◽  
2018 ◽  
Vol 53 (3) ◽  
pp. 275-282 ◽  
Author(s):  
Saadat Sarikhani Khorami ◽  
Kazem Arzani ◽  
Ghasem Karimzadeh ◽  
Abdolali Shojaeiyan ◽  
Wilco Ligterink
Keyword(s):  
Genetic Diversity ◽  
Genome Size ◽  
Plant Genetic Resources ◽  
Kernel Weight ◽  
High Yield ◽  
Phenotypic Analysis ◽  
High Genetic Diversity ◽  
Breeding Programs ◽  
Superior Genotypes ◽  
Southwest Of Iran

Plant genetic diversity is the fundamental of plant-breeding programs to improve desirable characteristics. Hence, evaluation of genetic diversity is the first step in fruit-breeding programs. Accordingly, the current study was carried out to evaluate 25 superior walnut genotypes in respect of phenotypic and cytological characteristics. For this purpose, 560 walnut genotypes in southwest of Iran were evaluated based on UPOV and International Plant Genetic Resources Institute (IPGRI) descriptor. After a 2-year primary evaluation, 25 superior genotypes were selected for future phenotypic and genome size assessment. Flow cytometry was used to estimate genome size of the selected superior genotypes. A high genetic diversity was found in walnut population collected from the southwest of Iran. The selected superior genotypes had high yield, lateral bearing, thin-shell thickness (0.90–1.64 mm), high nut (12.54–19.80 g) and kernel (7.02–9.91 g) weight with light (L) to extra light (EL) kernel color which easily can be removed from the shell. Also, FaBaCh2 genotype turned out to be protogynous being important as a pollinizer cultivar. In addition to extensive phenotypic analysis, genome size was determined. The studied genotypes were diploid (2n = 2x = 32) and varied in genome size from 1.29 (FaBaAv2) to 1.40 pg (FaBaNs12). Correlation analysis showed that lateral bearing, budbreak date, nut size, and weight were the main variables contributing to walnut production. A linear relationship was found between genome size and nut weight (r = 0.527**), kernel weight (r = 0.551**), and nut size index (NSI) (r = 0.487**). Therefore, genome size can be considered as a strong and valuable tool to predict nut and kernel weight and nut size.

Pre-clinical development of cell culture (Vero)-derived H5N1 pandemic vaccines

2008 ◽  
Vol 389 (5) ◽  
Author(s):  
M. Keith Howard ◽  
Otfried Kistner ◽  
P. Noel Barrett
Keyword(s):  
Cell Culture ◽  
High Yield ◽  
Wild Type Virus ◽  
Effective Vaccine ◽  
Type Virus ◽  
Wild Type ◽  
Yield Production ◽  
Homologous Virus ◽  
Clade 1 ◽  
Influenza H5n1

AbstractThe rapid spread of avian influenza (H5N1) and its transmission to humans has raised the possibility of an imminent pandemic and concerns over the ability of standard influenza vaccine production methods to supply sufficient amounts of an effective vaccine. We report here on a robust and flexible strategy which uses wild-type virus grown in a continuous cell culture (Vero) system to produce an inactivated whole virus vaccine. Candidate vaccines based on clade 1 and clade 2 influenza H5N1 strains, produced at a variety of manufacturing scales, were demonstrated to be highly immunogenic in animal models without the need for adjuvant. The vaccines induce cross-neutralising antibodies and are protective in a mouse challenge model not only against the homologous virus but against other H5N1 strains, including those from other clades. These data indicate that cell culture-grown, whole virus vaccines, based on the wild-type virus, allow the rapid high-yield production of a candidate pandemic vaccine.

scholarly journals Pseudomonas aeruginosa Rugose Small-Colony Variants Have Adaptations That Likely Promote Persistence in the Cystic Fibrosis Lung

2009 ◽  
Vol 191 (11) ◽  
pp. 3492-3503 ◽  
Author(s):  
Melissa Starkey ◽  
Jason H. Hickman ◽  
Luyan Ma ◽  
Niu Zhang ◽  
Susan De Long ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Pseudomonas Aeruginosa ◽  
Intracellular Signaling ◽  
Tricarboxylic Acid Cycle ◽  
Gene Clusters ◽  
Wild Type ◽  
Phenotypic Analysis ◽  
Small Colony Variants ◽  
Airway Infections ◽  
Small Colony

ABSTRACT Pseudomonas aeruginosa is recognized for its ability to colonize diverse habitats, ranging from soil to immunocompromised people. The formation of surface-associated communities called biofilms is one factor thought to enhance colonization and persistence in these diverse environments. Another factor is the ability of P. aeruginosa to diversify genetically, generating phenotypically distinct subpopulations. One manifestation of diversification is the appearance of colony morphology variants on solid medium. Both laboratory biofilm growth and chronic cystic fibrosis (CF) airway infections produce rugose small-colony variants (RSCVs) characterized by wrinkled, small colonies and an elevated capacity to form biofilms. Previous reports vary on the characteristics attributable to RSCVs. Here we report a detailed comparison of clonally related wild-type and RSCV strains isolated from both CF sputum and laboratory biofilm cultures. The clinical RSCV had many characteristics in common with biofilm RSCVs. Transcriptional profiling and Biolog phenotypic analysis revealed that RSCVs display increased expression of the pel and psl polysaccharide gene clusters, decreased expression of motility functions, and a defect in growth on some amino acid and tricarboxylic acid cycle intermediates as sole carbon sources. RSCVs also elicited a reduced chemokine response from polarized airway epithelium cells compared to wild-type strains. A common feature of all RSCVs analyzed in this study is increased levels of the intracellular signaling molecule cyclic di-GMP (c-di-GMP). To assess the global transcriptional effects of elevated c-di-GMP levels, we engineered an RSCV strain that had elevated c-di-GMP levels but did not autoaggregate. Our results showed that about 50 genes are differentially expressed in response to elevated intracellular c-di-GMP levels. Among these genes are the pel and psl genes, which are upregulated, and flagellum and pilus genes, which are downregulated. RSCV traits such as increased exopolysaccharide production leading to antibiotic tolerance, altered metabolism, and reduced immunogenicity may contribute to increased persistence in biofilms and in the airways of CF lungs.

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