Comparative Analysis of Low Lander Transcriptomes at Himalayas and Andes Reveals Differential Regulation of Erythropoiesis at Extreme Altitude

Systematic human expeditions to very high (≥ 3500 meters) and extreme altitudes (≥ 5500 meters) have documented marked changes in human physiology. However, only a handful of studies have reported lowlander transcriptome alterations at extreme altitudes. In this study, we compared the lowlander transcriptomes available in the literature for Chinese mountaineers (n=4, 3 males and 1 female)inthe Himalayas (Mount Xixabangma base camp, 5600 meters) and French mountaineers (n=8, all males) at Andes (La Rinconada, Peru, 5100 meters). We sought to find out significantly alteredpathways, gene networks, andtranscription factors (TFs) for each data set. We observed profound upregulation of GATA1 in the Himalaya transcriptome data set (+ 1.38-fold) in comparison tothe Andes data set (-1.36-fold). Core transcriptome analysis revealed that GATA1 upregulated erythropoiesis genes like KLF1, HBD, HBG, EPB42, ALAS2, and AHSP in the Himalayan dataset in contrast to the Andean data set.We also observed contrasting expression profiles ofKLF1 in the Himalayas (+1.22-fold) and Andes (-1.15-fold)for lowlander populations and differential expression regulation of its downstream target genes like AHSP, ALAS2, SLC4A1, EPB42,HBG2, andHBB.We also observed upregulation of SP1 (+ 2.46-fold) in the Himalayan transcriptome as compared to the Andean transcriptome which also regulates erythropoiesis genes along with GATA1. Our results indicate profound upregulation of erythropoiesis-promotingTFs and genes in Chinese mountaineers at extreme altitudes in contrast to French mountaineers at similar altitudes. Though our present analysis does not provide possible reasons for the observed differences inhypoxia-responsive erythropoiesis gene signatures, it certainly highlights ethnicity-dependenttranscriptome level variations in lowlanders at extreme altitudes

Caspase-3 like Protein in Wheat- <i>Tilletia indica </i>Dual Culture System as Potential Biomarker for Host Resistance to Kamal Bunt

596-602Immuno-histochemical staining of dual co-cultured calli of wheat-Tilletia indica having resistant and susceptible line using anti-mycelial and anti-teliospore polyclonal antibodies revealed the differential resistance response as indicated by pathogen invasion, mycelial colonization, plasmolysis and immunolocalization of chlamydospore like structures. The p53and caspases, crucial proteins of cell death pathways were detected by immunological procedures using heterologous immunoprobes in fungal colonized wheat calli. There was no difference in p53expression in resistant and susceptible lines at different days after inoculation (DAI) of T. indica on calli raised from mature embryos. The expression of p53started 14 DAI, increased steadily up to 21 DAI and became constant at 30 DAI showing the saturation of expression level. Studies on the expression of caspases revealed the absence of caspase-I like protein at different stages of growth. The caspase-3 like protein was induced at 3 DAI in both hosts and its expression steadily increased at 14 DAI and reached a plateau at 21 DAI. A remarkable difference in the level of expression of this protein between resistant and susceptible co-cultured calli was observed. Differential activation of caspase-3 like protein was observed in 10 hosts and non-hosts. It was found to be correlated with the degree of susceptibility and the expression of resistance at cellular level. Hence, it could be used as a potential biomarker for identification of Karnal Bunt resistance sources

Presence of stable carbon centric free radicals and ferromagnetic elements in the antennae and the wings of nocturnal silk moth: a magnetic nanostructure for magneto sensing

This work addresses an interesting, interdisciplinary problem of nature- “the mechanism by which animal senses the earth's magnetic field and navigate”. Currently there are two existing theories trying to explain, “How the animal senses the magnetic field of earth”. One theory is based on the presence of biogenic magnetic materials in the body of the animals. Such magnetic materials which are present inside the body, orients itself according to the earth's weak magnetic field and convey the information to the nervous system to develop the navigational map. The second theory is based on a light dependent photochemical reaction. A photochemical reaction leads to the generation of radical pairs, which helps in sensing the weak magnetic field of the earth. In this work, we are proposing a new model of magnetoreception. Unlike the existing radical pair system of magnetoreception, where a light-dependent reaction is essential to generate free radicals, here we show the presence of a large pool of stable carbon-centric free radicals in the nano-domains of the antennae and the wings of silk moth. This stable pool of carbon-centric free radicals is intrinsic in the nano-domains of these anatomical structures and responds to weak magnetic fields similar to that of Earth's (50 μT) even in the absence of light. Hence we are proposing that nocturnal animals in their navigation could utilize such a light independent mechanism. We further observed the presence of ferromagnetic elements (Fe, Ni, Co, Mn) in these structures. In conclusion, we have discussed how carbon centric free radicals along with other ferromagnetic components present in the antennae and the wings of the nocturnal silk moth, might help them to avoid the bats

Acute exposure of 532 nm laser differentially regulates skin tissue transcription factors.

High energy laser, particularly 532 nm, is widely used in defense and medical applications and there is need to address its occupational safety. Thermal and non-thermal effects of 532 nm high energy laser on skin are cause of concern. This study indicates impact of 532 nm laser on rat skin and first of its kind of attempt to understand transcriptional activation of genes as an early response following laser exposure. Skin of experimental rats were exposed to 532 nm radiance at 0.1, 0.25 and 0.50 W/cm2 for 10 sec. Thermographic changes of skin exposed to 532 nm laser exhibited increased Tmax temperature in radiance dependent manner. After thermal imaging, skin of experimental rats was collected 1 h post laser exposure for studying differential gene expression. The skin exposed to lower power density (0.1 W/cm2) did not show significant changes in expression of gene pathways studied. At moderate radiance (0.25 W/cm2), predominantly canonical wnt/B-catenin pathway genes notch1, axin2, ccdn1, wnt5a and redox homeostasis genes; txn1, nqo1 and txnrd1 were expressed. At higher radiance (0.5 W/cm2), significant repression of genes related to wound healing process particularly notch/wnt pathway viz. hes5, wnt1, wn3b with higher expression of dab2 was recorded. The data obtained from these studies would help in drawing safety limits for skin exposure to 532 nm laser. Further, genes expressed at moderate and high level of radiance exposure to skin were distinct and differential and provide new avenue to configure pathway to counteract laser induced delay in tissue injury and hair follicular damage

Fluorescent silk cocoon creating fluorescent diatom using a “water glass-fluorophore ferry”

Fluorophores are ubiquitous in nature. Naturally occurring fluorophores are exceptionally stable and have high quantum yield. Several natural systems have acquired fluorescent signature due to the presence of these fluorophores. Systematic attempt to harvest these fluorophores from natural systems could reap rich commercial benefit to bio-imaging industry. Silk cocoon biomaterial is one such example of natural system, which has acquired a fluorescent signature. The objective of this study is to develop simple, rapid, commercially viable technique to isolate silk cocoon membrane fluorophores and exploring the possibility of using them as fluorescent dye in bio-imaging. Here, we report an innovative water glass (Na₂SiO₃) based strategy to isolate the silk cocoon fluorophores. Isolated fluorophore is majorly quercetin derivatives and exhibited remarkable photo- and heat stability. Fluorescence and mass spectrometric analysis confirmed presence of a quercetin derivative. We further used this fluorophore to successfully label the silicate shell of diatom species Nitzschia palea

Carbondioxide gating in silk cocoon

Silk is the generic name given to the fibrous proteins spun by a number of arthropods. During metamorphosis, the larva of the silk producing arthropods excrete silk-fiber from its mouth and spun it around the body to form a protective structure called cocoon. An adult moth emerges out from the cocoon after the dormant phase (pupal phase) varying from 2 weeks to 9 months. It is intriguing how CO₂/O₂ and ambient temperature are regulated inside the cocoon during the development of the pupa. Here we show that the cocoon membrane is asymmetric, it allows preferential gating of CO₂ from inside to outside and it regulates a physiological temperature inside the cocoon irrespective of the surrounding environment temperature. We demonstrate that under simulating CO₂ rich external environment, the CO₂ does not diffuse inside the cocoon. Whereas, when CO₂ was injected inside the cocoon, it diffuses out in 20 s, indicating gating of CO₂ from inside to outside the membrane. Removal of the calcium oxalate hydrate crystals which are naturally present on the outer surface of the cocoon affected the complete blockade of CO₂ flow from outside to inside suggesting its role to trap most of the CO₂ as hydrogen bonded bicarbonate on the surface. The weaved silk of the cocoon worked as the second barrier to prevent residual CO₂ passage. Furthermore, we show that under two extreme natural temperature regime of 5 and 50 °C, a temperature of 25 and 34 °C respectively were maintained inside the cocoons. Our results demonstrate, how CO₂ gating and thermoregulation helps in maintaining an ambient atmosphere inside the cocoon for the growth of pupa. Such natural architectural control of gas and temperature regulation could be helpful in developing energy saving structures and gas filters