Molecular Genetic Experiment : Biology Lab

4)++ As shown in the following figure, plant cell cytokinesis differs from animal cell cytokinesis because

The basic plant life cycle with alternation of generations is modified in angiosperms by the change of haploid (n) and diploid (2n) generations, which take turns making each other.

Triggers production of other hormones, particularly ethylene and ABA, leading to leaf, abscission, abnormal growth, growth inhibition, and cell death

During testing our developed primers in August 2015, I began work on my Honor’s Thesis to understand mRNA expression changes during a common chemical treatment used by many growers to change the sex of the plant for seed production. Through growing female plants and treating some branches with silver thiosulfate, these plants will produce both male and female flowers, which can be harvested throughout the growing process. These flowers will have RNA extracted at three time points, which will then be processed, sequenced and

As seen from the given figure, the paper discovered that a single promoter (pFLS2) differentially drove gene expression in response to different stimuli using transcription fusion of pFLS2 with GUS. Specifically, they discovered that in the control treatment, pFLS2 was solely visible in root late elongation. While incubation with flg22 led to an increase Pfls2 activity in the root tip extending to the cortical cells, salylic acid (SA) showed strong blue staining in the vasculature, next H2O2 or the ethylene precursor ACC provoked an almost identical promoter activity in the root cap, root meristem and root epidermal cells, also finding pFLS2 is auxin responsive. Revealing that flg22, SA, H2O2 and ethylene all induce the expression of activity of the pFLS2 but the responses are specific to different tissue layers in the root. Overall proving evidence that a single promoter can drive expression to different tissues because of cis-regulatory elements, presenting observations showing that FLS2 is subject to positive regulation between receptor

Cytokinins move up the plant through the xylem. Whereas, auxins move down the plant. Cytokinins works with Auxin to control cell differentiation. The many functions of cytokinins include stimulation of germination, promote cell division, and plant growth. This hormone helps result in plant growth because they are able to release buds from apical dominance. Essentially, if a plant contains more cytokinins that means more mitosis is occurring and if more mitosis is occurring that means more cells are being produced and if more cells are being produced that means the plants

Making the onion tip root cell slide was successful. Our results supported the hypothesis because we saw cells in the onion root tip in prophase, metaphase, and anaphase. As we went up in power objectives, each phase of the cell became more definitive. The cell root was a great indicator of the structures of the different cycles of the cell. This is important because we will be prepared for future labs working with the microscopes and can now adjust it for the best view of the slide. We practiced working with the compound light microscopes and different phases of the cell cycle. Onion root tips are useful to observe mitosis because the cells are frequently diving as the root grows. So when we stained the cell, we caught many cells in different phases. The significance of this lab was to better understand the process and stages of mitosis and meiosis and compare and contrast the mitotic process in plants and animals. We grasped the concepts of what the chromosomes look like, and what they look like in each step of the processes. Having read much about mitosis and meiosis, seeing these cells was the real application of describing and understanding the stages.

The data I collected makes sense because I suspected that, if auxin concentration has an inverse effect on axillary bud growth, then as more auxin is applied apically, less bud growth will occur. These are the exact results I observed. What I found surprising was the growth I witnessed in the 5000 ppm group. I suspect one of the causes of this growth was experimental error or genetic mutations in the plants tested. Otherwise, I think the results for this experiment were successful in proving my hypothesis and confirming previous experiments done on the effects of auxin on axillary bud

In order to test this hypothesis, the team determined that the mor1 locus in a mutant A. thaliana plant caused temperature sensitive mutations in the development of microtubules when the temperature was increased from 21 C to 29 C. They used immunofluorescence microscopy, a technique that stains cell structures with a fluorescent dye, to visualize the actual microtubules of both wild type and mutant A. thaliana at different temperatures. The mutant A thaliana, were determined to contain two mutant alleles, each having "single amino-acid substitutions in the HEAT repeat nearest the N terminus." (Whittington 611) When exposed to temperatures of 29 C for a period of 90 minutes, the mutant samples displayed non-transverse orientation and "patchy diffuse fluorescence developed"¦eventually the microtubules became relatively short, sparse, and misaligned"¦" (Whittington 611) Normal

H3.3 is encoded by three HISTONE 3 RELATED (HTR) genes, HTR4 (At4g40030), HTR5 (At4g40040), and HTR8 (At5g10980), which are expressed in all tissues throughout the developmental stages (Okada et al., 2005). Wollmann and colleagues studied function of the H3.3 in Arabidopsis by utilizing mutant lines (Wollmann et al., 2017). Since single and double mutant of H3.3 subfamily did not have phenotype, triple mutant was used for the study. h3.3 kd-1 and h3.3 kd-3 plants were smaller than wild type and had serrated leaf margin and decreased fertility (Figure 2). H3.3 knockdown caused a variety of pleiotropic effects in plants possibly by changing the transcription. Thus, the impact of H3.3 knockdown on transcription was studied by using RNA-seq analysis. More than 900 genes were significantly mis-regulated in h3.3kd with the majority being downregulated (Figure. 2). Gene ontology term analysis (GO-Term) of downregulated genes revealed a large variety of response processes, including environmental and endogenous stimuli. Wollmann and colleague demonstrated that H3.3 is not required for gene expression in a global scale but the loss of H3.3 directly or indirectly affects the expression of genes related to response to internal and external stimuli.

This data shows a strange outcome, in the hypothesis; it says that “If acid is introduced to the seed during germination, then the roots will not grow as long as the seeds that are given water”. This statement proves to be untrue, because the roots grew longer with stronger acid than weaker acid, and in some, cases, grew better with strong acid than it did in water. This may be true because of the acid growth theory. The acid growth theory states that auxins cause the elongation of stem cells by promoting wall loosening. It was determined that this wall loosening is caused by hydrogen ions. This idea and subsequent supporting data gave rise to the acid growth theory, which states that when exposed to auxins, susceptible cells excrete protons into the wall at an enhanced rate, which in turn decreases the pH in the wall. The lowered wall pH then activates the wall loosening process which is essentially doing the same thing as the auxin hormone.

WP1. Starting point of the project is the molecular analysis of Arabidopsis candidate DNA insertion lines (obtained from the NASC stock center) harbouring T-DNA insertions in the gene encoding HMGA. Typically seeds of a segregating population are

All living things contain DNA which contains genes. These genes determine our physical appearance and how the body functions. “Phenotype” refers to the physical characteristics inherited from parents and “genotype” is determined by the alleles present in a gene. There are two types of genotypes, homozygous and heterozygous, and there are two types of genes, dominant and recessive. Dominant genes are those whose alleles are represented by a capital letter and recessive are represented by a lowercase. The gene “Bb” is a heterozygous dominant gene, and “bb” homozygous recessive. Gregor mendel is the father of the modern study of genetics.

The chemical and reagents used for the extraction and quantitation of DNA were: Plant DNAzol (0.3ml/0.1g), 100% ethanol (100%: 0.225 ml/0.1 g, 75%: 0.3 ml/0.1 g), Chloroform (0.3 ml/0.1 g), Plant DNAzol-ethanol solution: Plant DNAzol, 100% ethanol (1:0.75 v/v), TE buffer (10 mM Tris, 1 mM EDTA pH 8.0), 1.2% agarose gel (Agarose, 1X TAE buffer), 6X loading buffer (glycerol, Tris/EDTA pH 8.0, ethidium bromide), .25X TAE buffer, Restriction enzymes and Restriction endonuclease buffers. All the chemicals used were quality grade. The restriction

To understand the timing of FLC activation in embryogenesis, the author first examine when FLC is reactivated using an FLC:: GUS reporter line. They found that FLC expression was activated in pro-embryo within 1 day after pollination and onwards from both non-vernalized parental plants and vernalized parental plants, despite that FLC expression is lower from vernalized plants than that from none-vernalized plants. These results were further confirmed by in situ mRNA hybridization. Then the author postulated that LEC1, a master embryo transcription factor and expressed in the pro-embryo and throughout embryogenesis, is a good candidate required for embryonic de novo FLC activation. To support their hypothesis, the author first introduced loss of function null lec1 allele in FRI-Col and found that this FLC-dependent later flowering phenotype was suppressed. Next, they crossed lec1 with FLC:: GUS line and found that FLC expression was suppressed in the pro-embryo stage and onwards. These results suggest that LEC1 reactivate FLC expression in early embryogenesis and onwards in non-vernalized plants. To explore whether LEC1 could reactivate FLC expression after parental vernalization, the FLC expression was traced for two generations in LEC1/lec1 seedlings by FLC-GUS reporter. FLC was fully activated in LEC1/lec1 before cold and silenced after vernalization, and the