Elucidating the genetic basis of bast fibre production in flax (Linum usitatissimum L.)

Flax is often considered a total utilization crop because of the potential to extract value from two distinct products - seeds and stem fibres. However, very little genetic information is available on flax fibre genetics in comparison to oil improvement studies. In order to gain a detailed understanding of genetic control of the fibre concentration and search for the possibilities of developing dual purpose flax lines using both seed oil and stem fibre, the following studies were initiated: The first study evaluated the fibre and oil-related traits in a recombinant inbred population derived from a cross between a fibre flax variety Viking and an oilseed flax genotype E1747 over multiple locations under western Canadian field conditions. The study confirmed the presence of a significant genotype by environment interaction (p < 0.01) for fibre concentration indicating selection for this trait will be challenging. However, a lack of significant correlation between fibre and oilseed characteristics in field trials was encouraging and strengthened the hypothesis that breeding dual purpose flax types for western Canada is possible. The study also identified potential recombinant inbred lines (RILs) with enhanced fibre concentration as well as oil characteristics for use in future breeding endeavors. The second study established an anatomical basis for further research into flax fibre improvement by studying differences between the stem anatomy of 14 diverse flax genotypes in the field and under controlled environments such as a growth chamber. The results from the study supported the use of controlled environments for the purpose of quick screening of high fibre containing genotypes, especially at the green capsule stage of plant growth. The results also indicated that it was possible to select high fibre oilseed flax lines based on anatomical markers such as average area of single fibre cells, total fibre area and fibre to stem area ratio. In the third study, 17 simple sequence repeat (SSR) and 2 cleaved amplified polymorphic sequences (CAPS) molecular markers were used to assess the extent of genetic variability in the Viking × E1747 RIL population. CAPS markers LuFAD3A and LuFAD3B had the highest marker trait association (p < 0.0001) with linoleic and linolenic acid concentration. SSR markers such as CV8824, 5B6 and LU32 were found to be associated with plant height, oil concentration and protein concentration respectively using single marker analysis and step wise regression analysis. The molecular study confirmed the importance of Viking × E1747 mapping population in identifying genes/ markers related to both fibre and oilseed related traits in flax. In the fourth study, global transcript profiling using cDNA - based microarrays was performed to identify differentially expressed fibre related transcripts between Viking and E1747. The largest group of transcripts (7 %) found more abundant in Viking relative to E1747 fell under the functional group of cell wall development using gene ontology (GO) analysis. Transcripts such as callose synthases, expansins, cytochrome P450, fasciclin-like arabino galactan proteins and β-galactosidases were highly abundant in Viking relative to E1747. The transcripts more abundant in E1747 relative to Viking were UDP – glucose glucosyltransferase, auxin repressed protein, ubiquitin conjugating enzyme, peroxidases and lipid transfer proteins. Quantitative real time PCR results confirmed the suitability of the microarray platform to accurately discriminate transcript profiles between the two diverse flax types. In conclusion, this research has provided a number of new insights into flax fibre genetics. This information lays the foundation for further genetic studies on flax bast fibres and will complement research on developing dual purpose flax varieties

Relationship between environmental sustainable development goals and sustainable tourism: current status and future prospects

In this paper, we examine the current trend in tourism literature about a possible link between sustainable tourism and the targets of the environmental sustainable development goals (ESDG) proposed by the United Nations. We conduct a systematic literature review and bibliometric analysis on a sample of 160 papers published between 2015 until March 2023. The sample papers are organized in four clusters, namely, environmental sustainability, types of sustainable tourism, geographical location, and research method. The findings suggest that tourism literature strongly focuses on sustainable tourism and acknowledges the importance of environment in the discussion related to sustainability of the sector. However, there is lack of initiative to examine the relation between sustainable tourism and its contribution toward the achievement of targets of the ESDGs. In addition, we find that OECD member states are performing better compared to non-members in achieving the sustainable development goal 7 and 13, which are the proxy for environmental sustainability in this study. We also find that case study is the most popular research method in this field. The identified research gap in these clusters allowed us to make a list of the future research agenda in relation to the link between ESDG and sustainable tourism. The findings of the paper show how to extend the existing literature in future to enrich the knowledge about the topic. In addition, the findings will guide policymakers to make necessary changes in the regulatory framework of the tourism sector for enhancing the sector’s contribution in achievement of the ESDG targets

Parity and Short-Term Estradiol Treatment Utilizes Similar Cellular Mechanisms to Confer Protection Against Breast Cancer

Background: Protective effect of early pregnancy and short-term estrogen treatment (STET), against breast cancer is well established. The underlying mechanisms are not well understood. In this study, we compared the mammary gland cellular microenvironment influenced/induced by parity and STET alongside age-matched controls. Methods: Parous, STET, and control rats were injected with N-methyl-N-nitrosourea at 15 weeks and monitored for the development of mammary cancer. A subset of 4 rats were killed five weeks post carcinogen treatment and mammary gland samples were isolated and subjected to molecular analysis. Results: Our results demonstrated a reduction in cell survival, extracellular matrix associated proliferation, hormonal and growth factor receptor pathways in the experimental groups compared to control rats. Moreover, concomitant reductions in the EMT markers along with cell migration regulators were also observed in parous and STET groups. Hormonal receptor such as GHR, PR, ERα and growth factor receptors IGFR, EGFR and erbB2 were down regulated in the treatment groups. Further analysis revealed that parity and STET drastically reduced the expression, activation of JAK2 and nuclear localization of STATs. Conclusion: Parity and STET by targeting major cell signaling pathways involved in cell survival, cell migration and cell death reduces the mammary tumor promoting environment

Targeting insulin-like growth factor 1 receptor inhibits pancreatic cancer growth and metastasis.

Pancreatic cancer is one of the most lethal cancers. Increasing incidence and mortality indicates that there is still much lacking in detection and management of the disease. This is partly due to a lack of specific symptoms during early stages of the disease. Several growth factor receptors have been associated with pancreatic cancer. Here, we have investigated if an RNA interference approach targeted to IGF-IR could be effective and efficient against pancreatic cancer growth and metastasis. For that, we evaluated the effects of IGF-1R inhibition using small interfering RNA (siRNAs) on tumor growth and metastasis in HPAC and PANC-1 pancreatic cancer cell lines. We found that silencing IGF-1R inhibits pancreatic cancer growth and metastasis by blocking key signaling pathways such AKT/PI3K, MAPK, JAK/STAT and EMT. Silencing IGF-1R resulted in an anti-proliferative effect in PANC-1 and HPAC pancreatic cancer cell lines. Matrigel invasion, transwell migration and wound healing assays also revealed a role for IGF-1R in metastatic properties of pancreatic cancer. These results were further confirmed using Western blotting analysis of key intermediates involved in proliferation, epithelial mesenchymal transition, migration, and invasion. In addition, soft agar assays showed that silencing IGF-1R also blocks the colony forming capabilities of pancreatic cancer cells in vitro. Western blots, as well as, flow cytometric analysis revealed the induction of apoptosis in IGF-1R silenced cells. Interestingly, silencing IGF-1R also suppressed the expression of insulin receptor β. All these effects together significantly control pancreatic cancer cell growth and metastasis. To conclude, our results demonstrate the significance of IGF-1R in pancreatic cancer

A Breast Tissue Protein Expression Profile Contributing to Early Parity-Induced Protection Against Breast Cancer

Background/Aims: Early parity reduces breast cancer risk, whereas, late parity and nulliparity increase breast cancer risk. Despite substantial efforts to understand the protective effects of early parity, the precise molecular circuitry responsible for these changes is not yet fully defined. Methods: Here, we have conducted the first study assessing protein expression profiles in normal breast tissue of healthy early parous, late parous, and nulliparous women. Breast tissue biopsies were obtained from 132 healthy parous and nulliparous volunteers. These samples were subjected to global protein expression profiling and immunohistochemistry. GeneSpring and MetaCore bioinformatics analysis software were used to identify protein expression profiles associated with early parity (low risk) versus late/nulliparity (high risk). Results: Early parity reduces expression of key proteins involved in mitogenic signaling pathways in breast tissue through down regulation of EGFR1/3, ESR1, AKT1, ATF, Fos, and SRC. Early parity is also characterized by greater genomic stability and reduced tissue inflammation based on differential expression of aurora kinases, p53, RAD52, BRCA1, MAPKAPK-2, ATF-1, ICAM1, and NF-kappaB compared to late and nulli parity. Conclusions: Early parity reduces basal cell proliferation in breast tissue, which translates to enhanced genomic stability, reduced cellular stress/inflammation, and thus reduced breast cancer risk

Hair & skin derived progenitor cells: In search of a candidate cell for regenerative medicine

Background & objectives: Skin is an established tissue source for cell based therapy. The hair follicle has been introduced later as a tissue source for cell based therapy. The ease of tissue harvest and multipotent nature of the resident stem cells in skin and hair follicle has promoted basic and clinical research in this area. This study was conducted to evaluate skin stem cells (SSCs) and hair follicle stem cells (HFSCs) as candidate cells appropriate for neuronal and melanocyte lineage differentiation. Methods: In this study, SSCs and hair follicle stem cells (HFSCs) were expanded in vitro by explant culture method and were compared in terms of proliferative potential and stemness; differentiation potential into melanocytes and neuronal lineage. Results: SSCs were found to be more proliferative in comparison to HFSCs, however, telomerase activity was more in HFSCs in comparison to SSCs. Capacity to differentiate into two lineages of ectoderm origin (neuronal and melanocyte) was found to be different. HFSCs cells showed more propensities towards melanocyte lineage, whereas SSCs were more inclined towards neuronal lineage. Interpretation & conclusions: The study showed that SSCs had differential advantage over the HFSCs for neuronal cell differentiation, whereas, the HFSCs were better source for melanocytic differentiation

Silencing IGF-1R alters ERK and STAT signaling in PANC-1 and HPAC cells.

<p>(A & C): The effect of IGF-1R suppression on ERK and STAT signaling was examined in pancreatic cancer cells. Whole cell lysates were separated by SDS-PAGE and analyzed by Western blot for expression levels of phospho-ERK, ERK, IR-β, phospho-IRS-1, IRS, phospho-STAT3, STAT3, COX-2 and β-actin. (B & D): Representative blots are presented and corresponding densitometric analysis is shown to the right of each image. PS-PANC-1 Scrambled, PI-PANC-1 IGF-1R silenced, HS-HPAC Scrambled, HI-HPAC IGF-1R silenced.</p

IGF-1R silencing inhibits invading ability and epithelial-mesenchymal transition of pancreatic cancer cells.

<p>(A) PANC-1 and HPAC cell invasion was assessed in transwell chambers coated with matrigel. Cells that invaded the matrigel-coated insert were fixed, stained and captured at 20× magnification. (B) Number of invaded cells were counted and expressed as percentage invasion. Experiments were done in triplicate (C) IGF-1R silencing inhibits expression of several epithelial-mesenchymal transition markers. Total protein lysates from scrambled control and IGF-1R silenced PANC-1 and HPAC cells were analyzed for expression of Notch-2, Snail, E-cadherin, N-Cadherin, Zeb, Vimentin, and Slug along with internal control β-actin. (D) Densitometic values of EMT markers are shown as % expression. PS-PANC-1 Scrambled, PI-PANC-1 IGF-1R silenced, HS-HPAC Scrambled, HI-HPAC IGF-1R silenced.</p