scholarly journals Transgenic Ectopic Overexpression of Broad Complex (BrC-Z2) in the Silk Gland Inhibits the Expression of Silk Fibroin Genes of Bombyx mori

Insects ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 374
Author(s):  
Jiangshan Cong ◽  
Cuicui Tao ◽  
Xuan Zhang ◽  
Hui Zhang ◽  
Tingcai Cheng ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Developmental Stages ◽  
Expression Patterns ◽  
Silk Gland ◽  
Silk Protein ◽  
Regulation Mechanism ◽  
Wild Type ◽  
Transgenic Lines ◽  
In The Wild ◽  
Broad Complex

Bombyx mori silk protein genes are strictly turned on and off in different developmental stages under the hormone periodically change. The broad complex (BrC) is a transcription factor mediating 20-hydroxyecdysone action, which plays important roles during metamorphosis. Here, we observed that two isoforms of BmBrC (BmBrC-Z2 and BmBrC-Z4) exhibited contrasting expression patterns with fibroin genes (FibH, FibL and P25) in the posterior silk gland (PSG), suggesting that BmBrC may negatively regulate fibroin genes. Transgenic lines were constructed to ectopically overexpress BmBrC-Z2 in the PSG. The silk protein genes in the transgenic line were decreased to almost half of that in the wild type. The silk yield was decreased significantly. In addition, the expression levels of regulatory factors (BmKr-h1 and BmDimm) response to juvenile hormone (JH) signal were inhibited significantly. Then exogenous JH in the BmBrC-Z2 overexpressed lines can inhibit the expression of BmBrC-Z2 and activate the expression of silk protein genes and restore the silk yield to the level of the wild type. These results indicated that BmBrC may inhibit fibroin genes by repressing the JH signal pathway, which would assist in deciphering the comprehensive regulation mechanism of silk protein genes.

A new class of mutations in Arabidopsis thaliana, acaulis1, affecting the development of both inflorescences and leaves

Development ◽  
1993 ◽  
Vol 118 (3) ◽  
pp. 751-764 ◽  
Author(s):  
H. Tsukaya ◽  
S. Naito ◽  
G. P. Redei ◽  
Y. Komeda
Keyword(s):  
Arabidopsis Thaliana ◽  
Apical Meristem ◽  
Developmental Stages ◽  
Temperature Shift ◽  
Wild Type ◽  
New Class ◽  
Group 4 ◽  
Consequent Reduction ◽  
In The Wild ◽  
Specific Temperature

We isolated and analyzed mutants of Arabidopsis thaliana, acaulis, with flower stalks that are almost absent or are much reduced in length. The mutations are divided between two loci, acaulis1 (acl1) and acaulis2 (acl2). The acl1-1 mutation has been assigned to linkage group 4 in the vicinity of locus ap2. The acl1-1 mutant showed premature arrest of the inflorescence meristem after the onset of reproductive development, followed by consequent reduction in the number of flower-bearing phytomers and therefore flowers. The apical meristem of the inflorescences was morphologically normal but its radius was about half that of the wild type. The acl1 mutants are also defective in the development of foliage leaves. Both defects could be rescued by growth at a specific temperature (28°C). The length of the cells in acl1-3 mutant was less than that in the wild type but the numbers of cells in leaves and internodes of acl1 mutants were calculated to be the same as those of the wild type. Thus, the defects in inflorescences and leaves were attributed to defects in the process of elongation (maturation) of these cells. Temperature-shift experiments showed that the Acl1+ product was necessary at all developmental stages. A critical stage was shown to exist for recovery from the cessation of development of inflorescence meristems that was caused by the acl1-1 mutation. Grafting experiments showed that the acl1-1 mutation does not affect diffusible substances. An analysis of double mutants carrying both acl1-1 and one of developmental mutations, ap1, clv1, lfy, or tfl1, showed that ACL1 is a new class of gene.

Pax6 regulates specification of ventral neurone subtypes in the hindbrain by establishing progenitor domains

Development ◽  
2002 ◽  
Vol 129 (6) ◽  
pp. 1327-1338 ◽  
Author(s):  
Masanori Takahashi ◽  
Noriko Osumi
Keyword(s):  
Expression Patterns ◽  
Domain Formation ◽  
Wild Type ◽  
Whole Embryo Culture ◽  
Neuronal Markers ◽  
Signalling Molecules ◽  
Neuronal Progenitors ◽  
In The Wild ◽  
Mutant Rat

Recent studies have shown that generation of different kinds of neurones is controlled by combinatorial actions of homeodomain (HD) proteins expressed in the neuronal progenitors. Pax6 is a HD protein that has previously been shown to be involved in the differentiation of the hindbrain somatic (SM) motoneurones and V1 interneurones in the hindbrain and/or spinal cord. To investigate in greater depth the role of Pax6 in generation of the ventral neurones, we first examined the expression patterns of HD protein genes and subtype-specific neuronal markers in the hindbrain of the Pax6 homozygous mutant rat. We found that Islet2 (SM neurone marker) and En1 (V1 interneurone marker) were transiently expressed in a small number of cells, indicating that Pax6 is not directly required for specification of these neurones. We also observed that domains of all other HD protein genes (Nkx2.2, Nkx6.1, Irx3, Dbx2 and Dbx1) were shifted and their boundaries became blurred. Thus, Pax6 is required for establishment of the progenitor domains of the ventral neurones. Next, we performed Pax6 overexpression experiments by electroporating rat embryos in whole embryo culture. Pax6 overexpression in the wild type decreased expression of Nkx2.2, but ectopically increased expression of Irx3, Dbx1 and Dbx2. Moreover, electroporation of Pax6 into the Pax6 mutant hindbrain rescued the development of Islet2-positive and En1-positive neurones. To know reasons for perturbed progenitor domain formation in Pax6 mutant, we examined expression patterns of Shh signalling molecules and states of cell death and cell proliferation. Shh was similarly expressed in the floor plate of the mutant hindbrain, while the expressions of Ptc1, Gli1 and Gli2 were altered only in the progenitor domains for the motoneurones. The position and number of TUNEL-positive cells were unchanged in the Pax6 mutant. Although the proportion of cells that were BrdU-positive slightly increased in the mutant, there was no relationship with specific progenitor domains. Taken together, we conclude that Pax6 regulates specification of the ventral neurone subtypes by establishing the correct progenitor domains.

scholarly journals Mutation of a palmitoyltransferase ZDHHC18-like gene is responsible for the minute wing mutation in the silkworm (Bombyx mori)

2017 ◽  
Author(s):  
Ye Yu ◽  
Xiaojing Liu ◽  
Xiao Ma ◽  
Zhongjie Zhang ◽  
Na Liu ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Positional Cloning ◽  
Molecular Mechanisms ◽  
Adult Stage ◽  
Significant Proportion ◽  
Gene Promoter ◽  
Wild Type ◽  
Evolutionarily Conserved ◽  
In The Wild ◽  
Hippo Signalling

AbstractPulpal- and adult-stage minute wing (mw) mutants of the silkworm Bombyx mori have much smaller wings than those of the wild type. Herein, we report the genetic and molecular mechanisms underling the formation of the minute wing. Fine mapping and positional cloning revealed that a palmitoyltransferase ZDHHC18-like gene (BmAPP）was responsible for the mw mutation. CRISPR/Cas9 screening of the BmAPP gene in wild-type embryos revealed that a significant proportion of adults had the mw mutation. In an mw mutant strain, u11, a 10-bp insertion in the promoter of a novel gene resulted in low-level translation of a protein belonging to the DHHC family. A PiggyBac-based transgenic analysis showed that the promoter induced the expression of aBmAPP gene promoter in the wild type but not the mw mutant. These findings indicate that functional deletion of this gene promoter accounts for the mw mutation in silkworm. The possibility that BmAPP gene is involved in Hippo signalling pathway, an evolutionarily conserved signaling pathway that controls organ size, is discussed.

scholarly journals Yellow nutsedge WRI3/4-like gene improves drought tolerance in Arabidopsis thaliana by promoting cuticular wax biosynthesis

2019 ◽  
Author(s):  
Chao Cheng ◽  
Shutong Hu ◽  
Yun Han ◽  
Di Xia ◽  
Bang-Lian Huang ◽  
...  
Keyword(s):  
Fatty Acid Biosynthesis ◽  
Phylogenetic Analyses ◽  
Cuticular Wax ◽  
Wild Type ◽  
Yellow Nutsedge ◽  
Transgenic Lines ◽  
In The Wild ◽  
Peg Treatment ◽  
Simulated Drought ◽  
Tag Accumulation

Abstract In this study we cloned a WRI1-like gene from yellow nutsedge. Conserved domain and phylogenetic analyses indicated it to be a WRI3/4-like gene. Arabidopsis plants transformed with WRI3/4-like gene showed significantly improved tolerance to both PEG-simulated drought stress and real dehydration compared with the wild type. Quantitative RT-PCR indicated that, under unstressed conditions, the expressions of key genes involved in fatty acid biosynthesis was not significantly different between wild type (WT) and transgenic lines, while the expressions of genes involved in cuticular wax biosynthesis was significantly higher in transgenic lines compared with the wild type. The PEG treatment slightly decreased the expression of above mentioned genes in WT plants while it was significantly increased in transgenic lines compared with their respective unstressed control. Without PEG treatment, the expression of TAG1, the gene involved in triacylglycerol (TAG) accumulation, was 10-40% lower in the transgenic lines than that in the wild type. However, after PEG treatment, the expression of TAG1 was slightly decreased in the wild type, while in the transgenic lines its expression was decreased by 20-70% compared with unstressed transgenic lines and was highly significantly lower than that in the wild type. The cuticular wax content in Arabidopsis leaves was significantly higher in the transgenic lines than that in the wild type, while the oil content was not significantly different.

scholarly journals Overexpression of TaCOMT Improves Melatonin Production and Enhances Drought Tolerance in Transgenic Arabidopsis

2019 ◽  
Vol 20 (3) ◽  
pp. 652 ◽  
Author(s):  
Wen-Jing Yang ◽  
Yong-Tao Du ◽  
Yong-Bin Zhou ◽  
Jun Chen ◽  
Zhao-Shi Xu ◽  
...  
Keyword(s):  
Drought Tolerance ◽  
Transgenic Arabidopsis ◽  
Triticum Aestivum L ◽  
Regulation Mechanism ◽  
Wild Type ◽  
Drought Treatment ◽  
Agricultural Applications ◽  
Transgenic Lines ◽  
Mda Content ◽  
Melatonin Production

Melatonin (N-acetyl-5-methoxytryptamine) is involved in many developmental processes and responses to various abiotic stresses in plants. Most of the studies on melatonin focus on its functions and physiological responses in plants, while its regulation mechanism remains unknown. Caffeic acid 3-O-methyltransferase (COMT) functions at a key step of the biosynthesis process of melatonin. In this study, a COMT-like gene, TaCOMT (Traes_1AL_D9035D5E0.1) was identified in common wheat (Triticum aestivum L.). Transient transformation in wheat protoplasts determined that TaCOMT is localized in cytoplasm. TaCOMT in wheat was induced by drought stress, gibberellin (GA)3 and 3-Indoleacetic acid (IAA), but not by ABA. In TaCOMT transgenic Arabidopsis, melatonin contents were higher than that in wild type (WT) plants. Under D-Mannitol treatment, the fresh weight of the transgenic Arabidopsis was significantly higher than WT, and transgenic lines had a stronger root system compared to WT. Drought tolerance assays in pots showed that the survival rate of TaCOMT-overexpression lines was significantly higher than that of WT lines. this phenotype was similar to that the WT lines treated with melatonin under drought condition. In addition, the TaCOMT transgenic lines had higher proline content and lower malondialdehyde (MDA) content compared to WT lines after drought treatment. These results indicated that overexpression of the wheat TaCOMT gene enhances drought tolerance and increases the content of melatonin in transgenic Arabidopsis. It could be one of the potential genes for agricultural applications.

Involvement of the Clock Gene period in the Circadian Rhythm of the Silkmoth Bombyx mori

2019 ◽  
Vol 34 (3) ◽  
pp. 283-292 ◽  
Author(s):  
Kento Ikeda ◽  
Takaaki Daimon ◽  
Hideki Sezutsu ◽  
Hiroko Udaka ◽  
Hideharu Numata
Keyword(s):  
Circadian Rhythm ◽  
Circadian Rhythms ◽  
Bombyx Mori ◽  
Negative Feedback ◽  
Masking Effect ◽  
Wild Type ◽  
Expression Levels ◽  
Knockout Strain ◽  
Behavioral Rhythms ◽  
In The Wild

In Lepidoptera, the roles of period ( per) and the negative feedback involving this gene in circadian rhythm are controversial. In the present study, we established a per knockout strain using TALEN in Bombyx mori, and compared eclosion and hatching rhythms between the per-knockout and wild-type strains to examine whether per is actually involved in these rhythms. The generated per knockout allele was considered null, because it encoded an extensively truncated form of PERIOD (198 aa due to a 64-bp deletion in exon 7, in contrast to 1113 aa in the wild-type protein). In this per knockout strain, circadian rhythms in eclosion and hatching were disrupted. Under LD cycles, however, a steep peak existed at 1 h after lights-on in both eclosion and hatching, and was considered to be produced by a masking effect—a direct response to light. In the per-knockout strain, temporal expression changes of per and timeless ( tim) were also lost. The expression levels of tim were continuously high, probably due to the loss of negative feedback by per and tim. In contrast, the expression levels of per were much lower in the per knockout strain than in the wild type at every time point. From these results, we concluded that per is indispensable for circadian rhythms, and we suggest that the negative feedback loop of the circadian rhythm involving per functions for the production of behavioral rhythms in B. mori.

Regulation of scute function by extramacrochaete in vitro and in vivo

Development ◽  
1994 ◽  
Vol 120 (12) ◽  
pp. 3595-3603 ◽  
Author(s):  
C.V. Cabrera ◽  
M.C. Alonso ◽  
H. Huikeshoven
Keyword(s):  
Expression Patterns ◽  
Transcription Activation ◽  
Loss Of Function ◽  
Wild Type ◽  
Helix Loop Helix ◽  
In The Wild ◽  
Yeast Assay ◽  
Number Of Cells

The pattern of adult sensilla in Drosophila is established by the dosage-sensitive interaction of two antagonistic groups of genes. Sensilla development is promoted by members of the achaete-scute complex and the daughterless gene whereas it is suppressed by whereas extramacrochaete (emc) and hairy. All these genes encode helix-loop-helix proteins. The products of the achaete-scute complex and daughterless interact to form heterodimers able to activate transcription. In this report, we show that (1) extra-macrochaete forms heterodimers with the achaete, scute, lethal of scute and daughterless products; (2) extramacrochaete inhibits DNA-binding of Achaete, Scute and Lethal of Scute/Daughterless heterodimers and Daughterless homodimers and (3) extramacrochaete inhibits transcription activation by heterodimers in a yeast assay system. In addition, we have studied the expression patterns of scute in wild-type and extramacrochaete mutant imaginal discs. Expression of scute RNA during imaginal development occurs in groups of cells, but high levels of protein accumulate in the nuclei of only a subset of the RNA-expressing cells. The pattern is dynamic and results in a small number of protein-containing cells that correspond to sensillum precursors. extramacrochaete loss-of-function alleles develop extra sensilla and correspondingly display a larger number of cells with scute protein. These cells appear to arise from those that in the wild type already express scute RNA; hence, extramacrochaete is a repressor of scute function whose action may take place post-transcriptionally.

scholarly journals Regulation of Hydrogen Peroxide-Dependent Gene Expression in Rhodobacter sphaeroides: Regulatory Functions of OxyR

2007 ◽  
Vol 189 (10) ◽  
pp. 3784-3792 ◽  
Author(s):  
Tanja Zeller ◽  
Mobarak A. Mraheil ◽  
Oleg V. Moskvin ◽  
Kuanyu Li ◽  
Mark Gomelsky ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Rhodobacter Sphaeroides ◽  
Expression Patterns ◽  
Class Iii ◽  
Wild Type ◽  
Binding Studies ◽  
Regulatory Pathways ◽  
Mutant Strains ◽  
In The Wild

ABSTRACT Genome-wide transcriptome profiling was used to reveal hydrogen peroxide (H2O2)-dependent regulatory mechanisms in the facultatively photosynthetic bacterium Rhodobacter sphaeroides. In this study we focused on the role of the OxyR protein, a known regulator of the H2O2 response in bacteria. The transcriptome profiles of R. sphaeroides wild-type and oxyR mutant strains that were exposed to 1 mM H2O2 for 7 min or were not exposed to H2O2 were analyzed. Three classes of OxyR-dependent genes were identified based on their expression patterns in the wild type of oxyR mutant strains with differing predicted roles of oxidized and reduced OxyR as activators of transcription. DNA binding studies revealed that OxyR binds upstream of class I genes, which are induced by H2O2 and exhibit similar basal levels of expression in the wild-type and oxyR mutant strains. The effect of OxyR on class II genes, which are also induced by H2O2 but exhibit significantly lower basal levels of expression in the wild-type strain than in the mutant, is indirect. Interestingly, reduced OxyR also activates expression of few genes (class III). The role of reduced OxyR as an activator is shown for the first time. Our data reveal that the OxyR-mediated response is fast and transient. In addition, we found that additional regulatory pathways are involved in the H2O2 response.

Molecular analysis of the hull-less seed trait in pumpkin: expression profiles of genes related to seed coat development11

2005 ◽  
Vol 15 (3) ◽  
pp. 205-217 ◽  
Author(s):  
Todd N. Bezold ◽  
Dennis Mathews ◽  
J. Brent Loy ◽  
Subhash C. Minocha
Keyword(s):  
Cell Wall ◽  
Seed Coat ◽  
Secondary Cell Wall ◽  
Expression Profiles ◽  
Expression Patterns ◽  
Lignin Biosynthesis ◽  
Molecular Data ◽  
Wild Type ◽  
In The Wild ◽  
Cell Wall Development

We undertook a comparative study of molecular changes during development of seed coats in the wild-type and a recessive hull-less mutant of pumpkin (Cucurbita pepo L.), with the goal of identifying key genes involved in secondary cell wall development in the testa. The mature mutant testa has reduced amounts of cellulose and lignin as compared to the wild type. The expression patterns of several genes involved in secondary cell wall biosynthesis during the development of the testa are described. These genes are: CELLULOSE SYNTHASE, PHENYLALANINE AMMONIA-LYASE, 4-COUMARATE-CoA LIGASE, and CINNAMOYL-CoA REDUCTASE. Additionally, the expression patterns of a few genes that were differentially expressed in the two genotypes during testa development (GLUTATHIONE REDUCTASE, ABSCISIC ACID RESPONSE PROTEIN E, a SERINE-THREONINE KINASE, and a β-UREIDOPROPIONASE) are presented. The results show a coordinated expression of several genes involved in cellulose and lignin biosynthesis, as well as marked differences in the level of their expression between the two genotypes during testa development. There is generally a higher expression of genes involved in cellulose and lignin biosynthesis in the wild-type testa as compared to the mutant. The molecular data presented here are consistent with anatomical and biochemical differences between the wild-type and the mutant testae. An understanding of the genes involved in cell wall development in the testa will facilitate the manipulation of seed coat development in Cucurbita and other species for diverse commercial applications.

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