Dear Steemians,
From this week onwards every Sunday, I will put forward few key discoveries published in journals in last 7 days. This is an attempt to bring discussions on biology in steemit platform. I shall focus on few key subject areas like, Molecular biology, Molecular Immunology, Biochemistry*, Neurosciences. I may diverge a bit if there is some paper which is much more exciting and not in the topic. I shall cite the sources appropriately so you can access the original articles and get a closer understanding. I hope to share my passion and curiosity for the subject with you my friends.
Weekly round up 26 Nov 2017.
What makes us more human than the primates?
Scientists at Yale have attempted to address this question using transcriptome sequencing of 16 regions of adult human, chimpanzee and macaque brains. Together with single cell sequencing and histological analysis; Anintegratedd map of gene expression was created and was used to understand the differences across species.
The authors suggest the following key findings.
- Human specific genes include those encoding transcription factors, ion channels and neurotransmitter biosynthesis.
- Neuromodulatory systems show broad expression differences between species. They show that dopamine biosynthesis genes are enriched in human striatum and neocortex. These transmitters are involved in distinct human aspects like Cognition and behaviour, reasoning, working memory etc.,
Source: Molecular and cellular reorganization of neural circuits in the human lineage; Science. Link
Percison genome engineering.
A group lead by David R. Liu has created a method to edit bases in the genomic DNA precisely and without DNA cleavage. Till now changes in bases were created with use of nucleases that cut open the DNA backbone and edit the bases either by inserition or deletion. The proposed method uses adenosine base editors (ABEs) that mediate the conversion of A-T to G-C in the genomic DNA. By using in-vitro selection techniques they coaxed bacteria to create enzymes that could correct and restore sequences to gain antibiotic resistance.
After seven rounds of evolutionary selection they were able to create enzymes that had high editing efficiency and in effect create a robust system which they test on rare diseases that have such base pair alterations.
Source: Programmable base editing of A•T to G•C in genomic DNA without DNA cleavage. Nature. Link
New candidate drugs for Alzheimers disease!
A recent resource paper published on cell reports has described a model method to use iPSC based screening of Pharmaceutical compounds for Aß phenotypes of AD. Aß is a peptide that is a cruical component of amyloid plaques found in the patients of alzhimers. In this study, Scientists used iPSC neurons derived from patients and and screened for a reduced Aß protein when treated with a large set of pharmaceutical components. They suggest that the identified compounds along with existing inhibitors of β- or γ-secretase will have desired effect to stall Alzheimers. The authors indicate a future study incluing possibility of clinical trials.
Source: iPSC-Based Compound Screening and In Vitro Trials Identify a Synergistic Anti-amyloid β Combination for Alzheimer’s Disease. Cell Reports. Link
Restoring lost function: An invitro model based on CRISPR/Cas9
Hans clevers has done it again!. The group lead by Clevers have derived organoids from Cystic fibrosis patients and using the 'recently developed' CRISPR/Cas9 genome editing system have corrected the genes. The corrected alleles expressed functional CFTR protein and there by reverting back to the non-diseased state. This proof of concept study pushes us to consider the future with percision genome editing tools to cure deadly heriditary diseases.
Source: Functional Repair of CFTR by CRISPR/Cas9 in Intestinal Stem Cell Organoids of Cystic Fibrosis Patients. Cell Stem Cell. Link
To be continued.
That is it for this weeks Biology round up. I hope i can churn out one every sunday. All your comments are much appreciated. If you would like to discuss with me on steemit.chat you are welcome to do that my profile name is my user name also. I am open to reccomendations and suggestions from the community. This is a small expreriment, to bring biology forward in Steemit.
- Biochemistry is not a subject I am an expert on. I will summarize an article that is interesting; you are free to request if you want a particular article. I will likely take it up on seperate post.
Image Sources: All the images used are attributed to the corresponding authors. They are not mine. Please take time to check their galleries as it gives them more exposure and you will get to know their work better.
Lung radiograph: Wikimedia commons
Lion Tamarin: Flickr/Steve wilson
