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Using tools increases foraging success in sea otters and protects their teeth from damage

Four new studies inform on the multistep path to generate broadly active HIV-1 antibodies

Comprehensive spatial planning in international waters is key to achieving ocean sustainability

Automated labs spread across the globe create, test, and assemble materials—no humans required

The decreasing cost of electricity worldwide from wind and solar energy, as well as that of end-use technologies such as electric vehicles, reflect substantial progress made toward replacing fossil fuels with alternative energy sources. But a full ...

Multiscale mechanical linkage elongates tissues in development

Cells and tissues acquire their shape and function during embryonic development. While the blueprint for tissue design is encoded in the genome, the execution of this program relies on the mechanical progression of coordinated behaviors at molecular, cellular, and tissue scales. Thus, understanding the emergence of biomechanical features and their functions in morphogenesis across multiple scales is fundamental to elucidating normal development and the mechanisms underlying congenital malformation.

My research has focused on convergent extension (CE), a conserved collective cell movement that elongates the head-to-tail body axis and several organ systems, including the neural tube, heart, and kidney. Recent studies have identified novel biomechanical features across multiple scales crucial to CE. Our data suggest that cellular forces propagate in a polarized manner, driving the propagation of coordinated cell movement. This multiscale mechanical linkage generates a synergistic effect, promoting efficient and robust body axis elongation. Conversely, subtle biomechanical compromises at the subcellular level can escalate over time and space, ultimately leading to axis elongation failure in the entire organism.

online TUESDAY

Zoom link: Join Zoom Meeting https://cam-ac-uk.zoom.us/j/87939943699 Meeting ID: 879 3994 3699

• Speaker: Shinuo Weng, Johns Hopkins University
• Tuesday 28 May 2024, 14:30-15:30
• Venue: online TUESDAY.
• Series: Morphogenesis Seminar Series; organiser: Jia CHEN.

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Cortical microtubules shape cell walls to support a wide range of functions

Abstract

How plants fulfill their life functions is to a large extend dictated by the presence of cell walls. These cell walls can adopt a wide range of structures, depending on the local functional demands—from stretching in a particular direction to reconciling contradictory requirements. A beautiful example of the latter is found in the primary xylem. Different patterns of local cell wall reinforcements are used at different stages of development, in line with different mechanical requirements. The required anisotropic material properties largely derive from the location and orientation of the constituting cellulose microfibrils. These, in turn are deposited along the cortical microtubule cytoskeleton.

I will describe how we use the banded pattern in protoxylem as a model system for complex cell wall patterns. For this, we use a diversity of modelling approaches involving both cortical microtubules and Rho-of-Plants (ROP) proteins. These deeply conserved small GTPases can establish membrane zones with different properties, leading to local differences in microtubule dynamics. Microtubules, however, do not simply “read out” this pattern. The final pattern arises from the mutual interations of both systems. This work not only helped us understand how these beautiful and functionally important patterns are formed, but also brought to light important insights on 1) how the precise distribution of microtubule nucleation plays a critical role in maintaining homogeneous microtubule arrays and, hence, cell wall integrity; and 2) how microtubule flexibility affects the array’s potential to adopt complex patterns and align in the first place.

I will also show some stunning pictures from recent field trips to South Africa and the USA to study/hunt for some very special plants: the few known species in the world that display dimorphic enantiostyly, which we use as a model system for the de novo establishment a left-right asymmetry. These plants demonstrate that rich biodiversity we still have in our world is an incredibly valuable resource even for fundamental cell and developmental biology, though challenging and challenged.

This is a hybrid event, in-person at SLCU and Zoom link: Join Zoom Meeting https://cam-ac-uk.zoom.us/j/87939943699 Meeting ID: 879 3994 3699

• Speaker: Eva Deinum
• Monday 10 June 2024, 14:30-15:30
• Venue: in person at Sainsbury Laboratory and online.
• Series: Morphogenesis Seminar Series; organiser: Jia CHEN.

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Wolfram Pönisch-Deciphering the role of noise in cell shape changes during epithelial-to-mesenchymal transition; Constance Le Gloanec-Protect and provide: the dual role of the cauline leaf.

Wolfram Pönisch – Postdoc in Lab of Ewa Paluch, PDN University of Cambridge

Title: Deciphering the role of noise in cell shape changes during epithelial-to-mesenchymal transition

Abstract: The development of an organism requires sequential state transitions towards more specialised cell types. Many state transitions coincide with changes in cell shape, with emerging evidence suggesting strong feedback between shape and state. An example of transitions where state and shape are tightly coupled is epithelial-to-mesenchymal transition (EMT) which plays a crucial role in development and pathogenesis. While the changes in gene expression driving EMT have been extensively studied, the cell shape dynamics during EMT remain poorly understood.

To address this challenge, we developed a morphometric pipeline employing spherical harmonics descriptors to represent 3D cell morphodynamics in a low-dimensional morphospace quantitatively. Combining live-cell imaging with this pipeline, we characterised the cell shape trajectories associated with EMT . We inferred the underlying stochastic morphodynamics by modelling shape dynamics as a Langevin process and characterised the cell shape noise. Our findings reveal a peak in noise coinciding with a transition from epithelial to mesenchymal attractor states. Molecular perturbation experiments and mathematical modelling suggest that an increase in actin protrusivity and a decrease in membrane tension account for the cell shape noise during EMT . Together, our study suggests that EMT -associated cell spreading can be described as a transition between morphospace attractors.

Constance Le Gloanec, NUS

Title: Protect and provide: the dual role of the cauline leaf

Abstract: Plant organs have evolved diverse shapes for specialized functions despite emerging as simple protrusions at the shoot apex. Cauline leaves serve both as photosynthetic organs and protective structures for emerging floral buds. However, their growth patterns remain elusive. Here, we investigate the developmental dynamics shaping cauline leaves underlying their functional diversification from other flat organs. We show that cauline leaves display a strong delay in overall elongation as compared to juvenile leaves. Using live-imaging, we reveal that their functional divergence hinges on early modulation of the timing of cell differentiation and cellular growth rates. In contrast to rosette leaves and sepals, cell differentiation is delayed in cauline leaves, fostering extended proliferation, prolonged morphogenetic activity, and growth redistribution within the organ. Notably, cauline leaf growth is transiently suppressed during the early stages, keeping the leaf small and unfolded during the initiation of the first flowers. Our findings highlight the unique developmental timing of cauline leaves, underlying their shift from an early protective role to a later photosynthetic function.

Zoom link: Join Zoom Meeting https://cam-ac-uk.zoom.us/j/87939943699 Meeting ID: 879 3994 3699

• Speaker: Constance Le Gloanec and Wolfram Pönisch
• Monday 03 June 2024, 14:30-15:30
• Venue: Online.
• Series: Morphogenesis Seminar Series; organiser: Jia CHEN.

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Some aspects of contact line dynamics with applications to flow in porous materials

Among the most difficult issues in CFD is the very wide range of scales involved in some problems. Attempts at investigating the dynamics contact line have been made coming from various theoretical and numerical frameworks, the closest to first principles being molecular dynamics, while diffuse interface methods and sharp interface methods with several variants have also been put forward. Experiments are obviously difficult. Efforts made on a number of typical cases, including plunging and withdrawing plates, a sheared droplet, sessile droplets on oscillating or accelerating substrates, menisci in nanopores and the hydrodynamics assist problem. The issues involved in nucleate boiling and accelerated sessile droplets will be addressed both from the point of view of experiments (performed by various colleagues from MIT and Tokyo University) and from the point of view of simulations.

I will also show recent developments in the Basilisk code allowing to simulate contact lines on complex curved boundaries, using the immersed boundary method and an appropriate contact angle boundary condition, and inside porous media.

• Speaker: Stephane Zaleski, Institut Jean Le Rond ∂’Alembert, Sorbonne Université
• Thursday 23 May 2024, 11:30-12:30
• Venue: Open Plan Area, Institute for Energy and Environmental Flows, Madingley Rise CB3 0EZ.
• Series: Institute for Energy and Environmental Flows (IEEF); organiser: Catherine Pearson.

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Studying cardiac effects of extreme exercise could yield clues to atrial fibrillation

University of Cambridge's Park Farm hosted one of the most important new agricultural events on the UK farming calendar this month.  

Night bikers deliver meds and cholera sleuths persist as gangs dominate life and landscape

Modelling ocean connectivity and future change at the Antarctic margins

Many Antarctic margin processes are changing including accelerated rates of ice sheet mass loss and a slowdown in the production of dense bottom waters. Although these changes are localised around the Antarctic continent, they have the potential to remotely disrupt downstream processes of climatic importance via advective connections along the shelf. In the first part of this talk I will present some work from my PhD thesis that investigates ocean connectivity around the Antarctic margins from a modelling perspective. The results from this work suggest there is widespread zonal connectivity between adjacent regions of the shelf, and that such connectivity is important to consider when interpreting and linking observed changes with upstream drivers. In the second part of the talk I will present results from simulations that investigate future climate-driven changes to Antarctic margin processes under different emission scenarios, with and without future freshwater contributions. Such changes are poorly constrained because many climate models fail to adequately resolve key features of the Antarctic margin including the narrow westward flowing currents, and the formation of both dense and abyssal water masses. Results from these simulations suggest that even under a mid-range emissions scenario without additional meltwater forcing, substantial changes in Antarctic continental shelf circulation and hydrography are possible by the end of this century.

• Speaker: Hannah Dawson, University of Tasmania
• Wednesday 22 May 2024, 13:00-14:00
• Venue: BAS Seminar Room 1; https://bas-ac-uk.zoom.us/j/91268978510.
• Series: British Antarctic Survey - Polar Oceans seminar series; organiser: Dr Birgit Rogalla.

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Universities could no longer store Medicare and Medicaid data, and costs for many researchers would rise

Seminar – Population nutrition: upstream/downstream

All are invited to the MRC Epidemiology Seminar:

Population nutrition: upstream/downstream

Professor Pablo Monsivais, Washington State University

This hybrid seminar will be held in Institute of Metabolic Science seminar rooms 1 & 2, Level 4, Wellcome-MRC Institute of Metabolic Science, Addenbrooke’s Hospital, Cambridge, CB2 0QQ , and online.

If attending online, please register at https://mrc-epid.zoom.us/meeting/register/tJIqf-moqD4iEtOSgtPiXJanoInqfmdkhdG2#/registration

About this talk In this presentation, Professor Monsivais will review two interdisciplinary projects aimed at identifying population-level determinants of diet and one project developing heart-healthy ready meals for use in research studies and interventions.

About Professor Monsivais After doctoral and post-doctoral training in neuroscience and physiology at the University of Washington and University College London, Professor Monsivais returned to the University of Washington to retrain in nutrition and public health in 2004.

Between 2007 and 2011, he conducted behavioral and epidemiologic research on food choices, diet and health at the UW’s Centre for Public Health Nutrition in the School of Public Health, first as a postdoctoral fellow in behavioral sciences and then as an acting assistant professor in the Department of Epidemiology. From 2011 to 2017 he was Senior University Lecturer at the University of Cambridge Centre for Diet and Activity Research where he led a research group focused social and behavioral epidemiology.

He is currently an Associate Professor at the Elson S. Floyd College of Medicine based at Washington State University.

• Speaker: Speaker to be confirmed
• Wednesday 15 May 2024, 13:15-14:15
• Venue: MRL meeting rooms 1 & 2, Level 4 Institute of Metabolic Sciences, Addenbrooke’s Treatment Centre (ATC) .
• Series: MRC Epidemiology and CEDAR Seminars; organiser: Paul Browne.

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Cortical microtubules shape cell walls to support a wide range of functions

Abstract

How plants fulfill their life functions is to a large extend dictated by the presence of cell walls. These cell walls can adopt a wide range of structures, depending on the local functional demands—from stretching in a particular direction to reconciling contradictory requirements. A beautiful example of the latter is found in the primary xylem. Different patterns of local cell wall reinforcements are used at different stages of development, in line with different mechanical requirements. The required anisotropic material properties largely derive from the location and orientation of the constituting cellulose microfibrils. These, in turn are deposited along the cortical microtubule cytoskeleton.

I will describe how we use the banded pattern in protoxylem as a model system for complex cell wall patterns. For this, we use a diversity of modelling approaches involving both cortical microtubules and Rho-of-Plants (ROP) proteins. These deeply conserved small GTPases can establish membrane zones with different properties, leading to local differences in microtubule dynamics. Microtubules, however, do not simply “read out” this pattern. The final pattern arises from the mutual interations of both systems. This work not only helped us understand how these beautiful and functionally important patterns are formed, but also brought to light important insights on 1) how the precise distribution of microtubule nucleation plays a critical role in maintaining homogeneous microtubule arrays and, hence, cell wall integrity; and 2) how microtubule flexibility affects the array’s potential to adopt complex patterns and align in the first place.

I will also show some stunning pictures from recent field trips to South Africa and the USA to study/hunt for some very special plants: the few known species in the world that display dimorphic enantiostyly, which we use as a model system for the de novo establishment a left-right asymmetry. These plants demonstrate that rich biodiversity we still have in our world is an incredibly valuable resource even for fundamental cell and developmental biology, though challenging and challenged.

• Speaker: Eva Deinum
• Monday 10 June 2024, 14:30-15:30
• Venue: in person at Sainsbury Laboratory and online.
• Series: Morphogenesis Seminar Series; organiser: Jia CHEN.

Add to your calendar or Include in your list

Despite a half-century of advancements, global magnetic resonance imaging (MRI) accessibility remains limited and uneven, hindering its full potential in health care. Initially, MRI development focused on low fields around 0.05 Tesla, but progress halted ...

To fully understand how the human brain works, knowledge of its structure at high resolution is needed. Presented here is a computationally intensive reconstruction of the ultrastructure of a cubic millimeter of human temporal cortex that was surgically ...

The Hubbard model is an iconic model in quantum many-body physics and has been intensely studied, especially since the discovery of high-temperature cuprate superconductors. Combining the complementary capabilities of two computational methods, we found ...

Phonons play a crucial role in many properties of solid-state systems, and it is expected that topological phonons may lead to rich and unconventional physics. On the basis of the existing phonon materials databases, we have compiled a catalog of ...