Mechanics, Turing and the Quail
Vaishnav Manoj, Int MSc. (B20)
Abstract: Roux proposed that each cell’s fate is predetermined at every stage of development. Then Dreisch came along, separated the blastula, and showed it could form two complete embryos—shattering Roux’s idea. Later, Alan Turing, the father of computer science decided to become one of the greatest biologists of all time by hypothesizing the reaction-diffusion model of pattern formation. This sparked researchers all over to search for molecules that obey the model in various models and processes. Decades later, some questioned whether it had to be just chemicals driving these patterns. Could forces play a similar role? The idea lingered as theory, while quantitative microscopy quietly became a cornerstone for studying developmental biology.
Finally, in 2024, a breakthrough arrived. Right before gastrulation, the posterior region of the quail epiblast contracted while the anterior extended. With help from a theoretical physics team, an experimental biology lab provided one of the first experimental proofs of a mechanical analogue to Turing’s reaction-diffusion model. It took nothing more than a strand of hair, a few transgenic lines, and a microscope.
Pre-requisites: Blind faith that if you cut an early-stage embryo, you get two new embryos.
It takes only one AUG codon to start translation... Or does it?
Tanaya Kole, PhD Scholar
Abstract: Most of us learn that 'AUG' is the universal “start signal” for protein synthesis, but it’s not the whole story. Some genes, like Kgd4 and Grs1 in yeast, break the rules by starting translation with UUG codon instead of AUG codon. Surprisingly, these genes manage to produce two different protein versions—one starting with AUG and another upstream with UUG—from the same mRNA! So, how do ribosomes recognize these non-AUG start points? My research suggests that it’s not just luck. "Special" proteins working with the ribosome, seem to guide this process. To uncover these helpers, I used a new technique I developed, mRNA-Tethered Ribosome Interactome Profiling (mTRIP). This revealed that ribosomes engaging with these non-AUG codons recruit unique factors not seen in regular translation. This discovery shows that ribosomes are more versatile than we thought. They can adapt to non-standard signals, which might be nature’s way of creating flexibility in how proteins are made. And who knows? Maybe there’s an entire hidden world of non-AUG translations out there just waiting for us to discover!
18S rRNA G1412A mutation affects translation initiation fidelity and ribosomal biogenesis
A Akhil Kumar, PhD Scholar (B22)
Abstract: In the eukaryotes, the selection of the start codon and establishment of open reading frame is governed by the 40S ribosome along with the translation initiation factors and Met-tRNAiMet while scanning the mRNA from 5′ to 3′ direction. Eukaryotic translation initiation predominantly occurs at the AUG start codon. Defects in the translation initiation machinery leads to selection of non-AUG codons. The 40S ribosomal subunit is one of the key components of translational initiation machinery consisting of 33 ribosomal proteins and a single 18S rRNA. To understand the residues of 18S rRNA that are important for stringent start codon selection we performed mutagenesis studies and identified a mutation in the head region of 18S rRNA from Guanine at 1412th position to Adenine that shows slow growth. 18S rRNAG1412A mutation shows 3 fold more initiation at the UUG codon as compared to wildtype. Cells harboring 18S rRNAG1412A mutation tend to grow slower and repress the GCN4 translation (gcn- phenotype) under the nutritional stress. Interestingly the mutation also shows 40S biogenesis defect by accumulation of precursor 20S pre-rRNA. Further investigation will help to understand the molecular mechanism behind the defects.
Left-Right Asymmetry Establishment in Mammals
Nimal Archish Kannan, Int. MSc (B21)
Abstract: The development of an organism from a single cell is one of the most fascinating and complex processes to happen in nature. Understanding the ways in which bags of molecules replicate and divide to give rise to orderly shapes has been the focus of developmental biologists for centuries. One of the first things a developing embryo has to do is to break symmetry - it's crucial to know in which direction an organ should develop. For this, asymmetry should be established in the three axes of the embryo, and various methods are employed from the biological toolkit to do the same. In this talk, I will be explaining how an embryo distinguishes it's left from it's right in the context of mammals. Long story short, left-right symmetry is broken by the expression of a gene called Nodal on the left side. But again, how does the organism 'know' it's left side to do the same? Nobody wants two left feet, after all.
Aniket VR, Int. MSc (B20)
Abstract: This talk will delve into Kevin Gaston’s landmark review on biodiversity, authored by one of the founding figures in macroecology. Gaston’s work examines global patterns in biodiversity, their significance, and the complex relationships that govern ecosystem resilience and function. Studying these patterns is essential to understanding how species diversity and distribution impact ecosystem services, especially amid accelerating global change. Since the review’s publication 24 years ago, our grasp of these dynamics has deepened, revealing critical shifts in biodiversity and ecosystem stability. I will cover how insights into biodiversity’s role have evolved and discuss the ongoing impacts of global environmental change, underscoring the relevance of Gaston’s work today.
Ketki Kabir, Int. PhD (B24)
Abstract: Antimicrobial resistance (AMR) is an ominous threat that looms over all of humanity and life alike. Unregulated use of antibiotics in healthcare, agriculture, animal rearing, veterinary science and other aspects of health and sciences has led to increased prevalence of antibiotic resistance species of pathogens that are now impossible to eradicate once infected. In this talk, I will discuss the current situation of AMR, followed by talking about the pilot study I undertook to analyse the AMR levels in bacteria isolated from soil and plant samples in Mumbai, India. As antibiotics slowly start to lose their effect owing to AMR, it is imperative to look for therapeutic agents that can either work together with antibiotics or replace them. With regards to this, I will discuss one of the alternative therapies to antibiotics– use of Bacteriophages; share results of my research on the same, followed by a case study to emphasise the potential of Bacteriophages to treat some of the most resistant infections.
Rudra Pratap Swain, Int. MSc (B24)
Abstract: Zinc finger proteins are one of the most abundant proteins in living systems, especially humans. Zinc fingers have varied biochemical functions, from being involved in transcription to suppressing many diseases. Also their binding ability to DNA and selectivity to DNA offers novel methods to study their role on diseases, modification of zinc fingers can be applied in creating zinc finger nucleases which can be extensively used in gene editing. This talk presents a basic understanding of the structure and function of zinc fingers and also of the applications of synthetic zinc fingers.
A Simanchal Dora, PhD Scholar, SBS
Abstract: In many insect species, older workers are responsible for colony defense, often engaging in self-sacrificial behavior. Aging workers of Neocapritermes taracua, a termite species, do so by rupturing their bodies to release a toxic mixture of a substrate and the enzyme BP76. BP76 is a laccase, which accumulates in these termites throughout their lifespan and remains catalytically active even in solid form for several months. In this talk, I will explain the mechanism of enzymatic action in BP76 and using the recently published crystal structure, discuss the structural basis of its remarkable stability and activity.