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Biology subjects

Husain, Z.

Publications and source records attributed to Husain, Z..

5 recordsLinked to original sources

Bridging fungal resistance and plant growth through constitutive overexpression of Thchit42 gene in Pelargonium graveolens

Pelargonium graveolens essential oil possesses significant attributes, known for perfumery and aromatherapy. However, optimal yield and propagation are predominantly hindered by biotic stress. All biotechnological approaches have yet to prove effective in addressing fungal resistance. The current study developed transgenic geranium bridging molecular mechanism of fungal resistance and plant growth by introducing cassette 35S::Thchit42. Furthermore, 120 independently putative transformed explants were regenerated on kanamycin fortified medium. Primarily transgenic lines were demonstrated peak pathogenicity and antifungal activity against formidable Colletotrichum gloeosporioides and Fusarium oxysporum. Additionally, phenotypic analysis revealed [~]2fold increase in leaf size and [~]2.1fold enhanced oil content. To elucidate the molecular mechanisms for genotypic cause, De novo transcriptional profiles were analyzed to indicate that the auxin-regulated longifolia gene is accountable for augmentation in leaf size, and ZF RICESLEEPER attributes growth upregulation. Collectively, data provides valuable insights into unravelling the mechanism of Thchit42-mediated crosstalk between morphological and chemical alteration in transgenic plants. This knowledge might create novel opportunities to cultivate fungal-resistant geranium throughout all seasons to fulfil demand.

plant biology↗

In vitro direct regeneration and Agrobacterium tumefaciens mediated in planta transformation of Ocimum sanctum L.

Ocimum sanctum is a multipurpose herb with highly significant medicinal properties. An in vitro direct regeneration protocol for propagation of a valuable medicinal plant Ocimum sanctum, using petiole explants has been successfully developed. The protocol employed regeneration of shoots directly, without any intervening callus using Murashige and Skoog (MS) medium fortified with 3 mg L-1 BAP + 1 mg L-1 NAA. The maximum regeneration frequency of 98% with 9.6 shoots per explants was achieved. Agrobacterium tumefaciens mediated genetic transformation (ATMT) protocol (transient and stable) was established using LBA4404 strain harboring pBI121 with uid-A reporter gene and neomycin phosphotransferase (npt-II) as selection marker. The putative transformants were screened on MS with 50 mg L-1 kanamycin and subsequently rooted on the half-strength MS medium. The confirmation was done via polymerase chain reaction (PCR) using npt-II and gus-A gene-specific primers. The maximum stable transformation frequency 70% {+/-} 0.35. Thus, it is apparent that the established in vitro direct regeneration and ATMT method was suitable for integrating novel genes and modulating the metabolic flux for obtaining desired agronomic trait in planta.

plant biology↗

Equilin does not affect thyroid hormone signaling in the developing Xenopus laevis tadpole brain

Toxcast/Tox21 is a massive federally run research effort dedicated to better understanding the potential toxicity of thousands of compounds in a high throughput manner. Among this list of compounds is equilin, an estrogen-like compound that was flagged as a potential thyroid hormone agonist. Here we examine if equilin acts like a thyroid hormone agonist on cellular and molecular mechanisms of brain development in Xenopus laevis tadpoles. To examine the effect of equilin, tadpoles were divided into eight groups and received 4 days of exposure. The experimental groups were as follows: 1 L, 10 L, and 100 L of equilin, 1 L, 10M, and 100 M of 17-{beta} estradiol as an estrogen control, 15 g/mL thyroxine (T4) as a thyroid hormone control, and a no-exposure control. After 4 days of treatment, animals were treated with CldU to label dividing cells for 2hr and then euthanized in MS-222. After fixation, body length was measured and the brains dissected out. IHC was performed on brains for CldU to label proliferating neural progenitor cells. Brains were then whole-mounted and analyzed using confocal microscopy. We found that equilin did not increase the number of dividing progenitor cells in a T4-like manner. Instead, equilin decreased proliferation in a dose-dependent manner, as did estradiol. The same paradigm was performed separately staining for caspase-3 and h2ax, finding that equilin increased cell death in contrast to CNTL and T4. In another experiment, RNA was extracted from tadpole brains in each group and qPCR was performed to assess change in expression of thyroid hormone-sensitive genes, Equilin did not affect gene expression in a thyroid hormone-like manner. Our data indicate that equilin does not act as a thyroid hormone agonist in the Xenopus laevis nervous system but instead acts similarly to estradiol. Our data strongly suggest that equilin is not a TH disruptor, contrary to the findings of the ToxCast/Tox21 dataset.

neuroscience↗

The flavor enhancer maltol increases pigment aggregation in dermal and neural melanophores in Xenopus laevis tadpoles

Melanophores are pigmented cells that change the distribution of pigmented melanosomes, enabling animals to appear lighter or darker for camouflage, thermoregulation, and UV-protection. A complex series of hormonal and neural mechanisms regulates melanophore pigment distribution, making these cells a valuable tool to screen toxicants as a dynamic cell type that responds rapidly to the environment. We found that maltol, a naturally occurring flavor enhancer and fragrance agent, induces melanophore pigment aggregation in a dose-dependent manner in Xenopus laevis tadpoles. To determine if maltol affects camouflage adaptation, we placed tadpoles into maltol baths situated over either white or black background. Maltol induced pigment aggregation in a similar dose-dependent pattern regardless of background color. We also tested how maltol treatment compares to melatonin treatment and found that the degree of pigment aggregation induced by maltol is similar to treatment with melatonin, but the time course differs significantly. Last, maltol had no effect on mRNA expression of pro-opiomelanocortin or melanin concentrating hormone receptor in the brain, both of which regulate camouflage-related pigment aggregation. Our results suggest that maltol does not exert its effects via the camouflage adaptation mechanism nor via melatonin-based mechanisms. These results are the first to identify a specific toxicological effect of maltol exposure and rules out several mechanisms by which maltol may exert its effects on pigment aggregation.

pharmacology and toxicology↗

Axonal transport of an insulin-like peptide mRNA promotes stress recovery in C. elegans

Aberrations in insulin or insulin-like peptide (ILP) signaling in the brain causes many neurological diseases. Here we report that mRNAs of specific ILPs are surprisingly mobilized to the axons of C. elegans during stress. Transport of the ILP ins-6 mRNA to axons facilitates recovery from stress, whereas loss of axonal mRNA delays recovery. In addition, the axonal traffic of ins-6 mRNA is regulated by at least two opposing signals: one that depends on the insulin receptor DAF-2 and a kinesin-2 motor; and a second signal that is independent of DAF-2, but involves a kinesin-3 motor. While Golgi bodies that package nascent peptides, like ILPs, have not been previously found in C. elegans axons, we show that axons of stressed C. elegans have increased Golgi ready to package peptides for secretion. Thus, our findings present a mechanism that facilitates an animals rapid recovery from stress through axonal ILP mRNA mobilization.

neuroscience↗