#8 Histones Causing Cancer, Plant Sugar Lanes and Forest Fires Killing Millions...
A new blueprint showing the building of the phloem, the histone modification behind disease and disorder as well as forest fires in Brazilian wetlands killing millions.
🧬🔵Changes to Histones causes cancers?
Mutations to histone proteins are linked to neurological disorders and cancers.
A histone is a protein that provides structural support to the chromosome. Their function is key as it allows DNA molecules to be tightly packed as they wrap around complexes of the histone proteins and so are able to fit into the cell nucleus. A new study shows that mutations to these histone regulator proteins are linked to both neurodevelopment disorders as well as some cancers.
A protein; PHIP/BRWD2, binds to three different histone modifications that are associated with active gene expression - explaining it’s two sided impact stated Marc Morgan the lead author of the study. Too little of this protein leads to a neurodevelopmental disorder named Chung-Jansen syndrome. On the flip side, too much of this protein has been linked to cancer cell multiplication.
This outstanding discovery not only identifies a ground-breaking mechanism for chromatin interactions but could be essential in future methods of cancer and neurodevelopmental disorder treatment.
Histones often have modifications that can influence gene expression. The combination of DNA loops and histone spools are referred to as nucleosomes. Gene promoting modifications of nucleosomes can increase gene expression with silencers reducing expression. The mutations within the gene that codes for the mentioned PHIP/BRWD2 protein was previously unknown. The research team screened dozens of synthetic nucleosomes with specific modifications for an interaction with PHIP/BRWD2. This meant that the team introduced PHIP into an array of purified nucleosomes to see which PHIP bound to. This resulted in the research team identifying three histone modifications that are all associated with cell proliferation.
The investigators then examined actual cells to analyse protein interactions with DNA. It was found that the PHIP/BRWD2 interacted with locations where the same three histone modifications existed. It is then known that the PHIP protein binds to these sites and recruits a fellow complex. It is currently unknown as to how this complex affects the cell proliferation.
However these findings open up numerous new avenues of research both in the pathway as well as encouraging searching for other histone-protein related neurodevelopmental disorders.
Morgan stated that the “PHIP-associated Chung-Jansen syndrome appears to be fairly rare, but as diagnostic human genome sequencing becomes more widespread, new patients are being identified”. Mutations of histone regulator proteins are the cause of a large number of neurodevelopmental disorders. As a result it is possible that some of these syndromes are affecting similar pathways, should these pathways be in common, we might be able to design a therapy.” The key to this is to understand the molecular biology in more detail.
⛙Sugar Transport Lane…
Blueprint shows how plants build a sugar transport lane…
A phloem is simply a vascular tissue in plants which conducts sugars and other metabolic products downwards from the leaves. A tiny region on the root tip has been found responsible for orchestrating the growth of the complex network of vascular tissues that transports the needed sugars through the plants roots.
The detailed blueprint of how plants construct phloem cells reveals pivotal information of how root meristems coordinate distinct maturation phases of the phloem tissue.
Phloem is central to the plant function as it is highly interconnected through the plants body, responsible for transporting sugars, nutrients as well as a range of signalling molecules between the plants organs. A detailed understanding on how this network operates is important for future applications within the agriculture, forestry and biotechnology industry.
Plants roots continually elongate throughout a plants life - a term named indeterminate growth. This means that as the roots grow they add new tissue to the root tip. A continuous line of specialized phloem cells runs the length of the roots and delivers the primary nutrient, sucrose, to the organs in need. To fulfil this key role, phloem tissue must rapidly mature and develop so that it can supply sugars to the surrounding tissues.
The long standing problem has been a lack of knowledge in how a single instructive gradient of proteins can stage the construction phases across all the different specialised cell files, or metaphorical highway lanes, that are present in roots.
Following research from the past 15 years, universities have uncovered the central role of cell to cell communication and feedback mechanisms in vascular patterning. This new research shows how this needed single lane of phloem cells is constructed independently of the surrounding cells. Through dissecting each stage of the of the sugar transport service lane, their live imaging showed how the proteins that control the maturation gradient of the root, interact with the genetic machinery that specifically controls phloem development.
The first author, Dr Pawel Roszak said that “We have shown how global signals in the root meristem interact with the cell type specific factors to determine distinct phases of phloem development at the cellular resolution. Using cell sorting followed by deep, high-resolution single-cell sequencing of the underlying gene regulatory network revealed a "seesaw" mechanism of reciprocal genetic repression that triggers rapid developmental transitions.”
The group also showed how phloem development is staged over time, with early genetic programs inhibiting late genetic programs and vice versa. The research team showed how early phloem regulators instructed specific genes to split phloem cells into different subtypes.
Essentially, the “broad maturation gradients interfacing with cell-type specific transcriptional regulators to stage cellular differentiation is required for phloem development.” The team, through live imaging, have mapped the cellular events from the birth of the phloem cell to its final stage of differentiation into phloem sieve element cells. This allowed the team to uncover the genetic mechanisms that coordinate the cell maturation and to connect the timing of meristem maturation regulators.
The research team plan to further explore the evolution of these mechanisms and how the process seen here may be applied elsewhere in plants.
🔥Brazil Wildfires kill 17 Million…
Brazil wildfires killed an estimated 17 million animals…
Brazilian scientists in an attempt to calculate the animals killed in the Pantanal wetlands have counted a vast amount of dead species. A rough estimate of 17 million vertebrates - including reptiles, birds and primates are believed to have died.
The wildfires that caused this ran between January and November destroying roughly 30% of the tropical wetland in South America. The head of science at WWF Brazil stated that there were 22,000 separate fires recorded during that year. It is important to note that this region of wetland does burn naturally. However as with many natural processes and disaster, human induced effects have exacerbated the issue with the 2020 wildfires being described as “apocalyptic”. The typical cycle of burning and recovery was replaced with constant and restless burning. These fires were unusual due to their scale, it is believed that the mega drought the area experiences was the cause of the unprecedented scale of the fire.
The study occurred based of simply counting the bodies. Scientists were able to reach the wetland area withing 48 hours of the fires with all seen animal remains being counted and examined. Out of many found animals the team was able to identify the species of 300 animals. They then went on to extrapolate the total number of killed animals.
This is a perfect example of sampling, measuring a certain area, recording enough quality data to be able to estimate the total figures for a significantly larger area. Whilst it would be ideal to record data across the whole sample area, this is not practical and feasible for an area of wetland roughly 12 million acres. However scientists have questioned the accuracy of the figure as a result, stating that there is a large margin for error when extrapolating data over such a large geographical area. Nonetheless, this acts as a ball mark figure with the exact number arguably less important than the portrayed message.
This case study also shows the human impact on ecosystems. On a more localised scale, this study may encourage proper fire management strategies and policies, and on a more global scale show the direct damage of climate change and anthropogenically induced issues.
Weekly Topics
🏞️ Environmental
Bugs across globe learning to eat plastic
Hidden attributes of Sudan Arabi Camels
🐼 Conservation
Insects - How farmers can be better engaged in species conservation
Biodiversity and ecosystem function - Environmental conditions
Endangered Nigerian chimps on the brink
🦠 Disease and Illness
First model to predict lifetime heart failure risk
Interaction between gut bacteria and drugs on CV disease
Disarming a blood clotting protein prevents gum disease
😷 COVID
Immune response to seasonal coronavirus
COVID immunity study and green league ranking
Shark antibody like proteins neutralize COVID virus
🧪 Biochemistry
Could octopuses have come from outer space?
High enzymatic reactivity of reactive oxygen species
🔬 Evolution
Unexpected waterflea relationship - evolution examined
When humans are gone - will other animals evolve to take our place?
Species level timeline of Mammal evolution
🧬 Genetics
3% of Greenland residents have rare genetic mutation
Carnivores are more prone to cancer
Medusa fish - grouped by traits
📷 Weekly Camera Roll
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