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Developmental Biology @devbiol.bsky.social · 9h

From our #SpecialIssue on Avian model systems.
Full paper link: tinyurl.com/pw5s23js

The three-dimensional structure of medullary bone: Novel criteria for the identification of avian sex-specific bone tissue

Medullary bone is a fast-growing, ephemeral bone tissue found inside the bone cavities of female birds. Identifying this tissue in the bones of fossil…

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Developmental Biology @devbiol.bsky.social · 9h

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Micro-CT 3D structures provide new criteria can be used to identify medullary bone and female individuals in the avian fossil record.
Crane A H @gruiformabi.bsky.social, Baldry C J, Rankin K E, Clarkin C E @clarkinbonebiol.bsky.social, Williams K A, Gostling N J @neilgostling.bsky.social

Diagram showing he differences between a healthy female bird bone with medullary bone and a pathological bird bone with avian osteoporosis. For each there is a global scan of tibiotarsi whole bone in lateral view, a micro-CT 3D cube reconstruction, and microCT cubes highlighting osteocyte lacunae. In between a box with writing "Differences include: Structural anisotropy, Connectivity density, Trabecular thickness, Osteocyte lacunae orientation".

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Developmental Biology @devbiol.bsky.social · 1d

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The chicken embryo brings new insights into the tissue specific evolutionary role of WFDC1 during amniote development

-T Metzker-Pinto, YTH Tran, I Buzzatto-Leite, L Lok, JF Sampar, HF Carvalho, G del Monte-Nieto, LE Alvares

tinyurl.com/3abhm3d5

#SpecialIssue on Avian model systems

(A–B) WFDC1 expression pattern during chicken and mouse eye development, respectively. The developmental stages are indicated at the top of each image. Sagittal (Ai) and coronal (Aii-iv, Bi-v) sections were presented. (C–E) UMAP visualization of the mouse retina cells according to their transcriptome similarities, representing the cell type (C), embryonic day (D) and WFDC1 expression level (E).

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Developmental Biology @devbiol.bsky.social · 4d

From our #SpecialIssue on Avian model systems

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Developmental Biology @devbiol.bsky.social · 4d

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Proteomic analysis of chick embryonic heart in experimental hypoxia shows upregulation in anaerobic glycolysis, apoptosis-related proteins, cell adhesion proteins, and secretory activity

By David Sedmera, Eliska Drobna Krejci, Ondrej Nanka, and Adam Eckhardt

tinyurl.com/y3vdmx2s

STRING analysis of protein-protein interaction (106 proteins with significantly higher concentration in hypoxia) – divided to 7 clusters containing more than one protein. Compared to the genes downregulated in hypoxia, there are more numerous protein interactions, attesting to the activation of key pathways allowing the adaptation of the heart to hypoxic stress. The clusters are colour-coded; protein abbreviations correspond to their names

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Developmental Biology @devbiol.bsky.social · 4d

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Research facilities in the UK, France, and Japan maintaining transgenic lines for Avian developmental biology

By Lindsay Henderson, Yuya Okuzaki, Christophe Marcelle, Mike McGrew, and Ken-ichi Nishijima

tinyurl.com/4drw4d6a
#SpecialIssue on Avian model systems

Fluorescent microscopy images of transgenic chicken resources maintained at the NARF, The Roslin Institute. (A) GFP chicken embryo with a ‘red’ graft placed into the limb bud with micro-surgery. The graft is about 50–100 μM. (B) Stage 32 HH limb bud from the CSF1R-eGFP embryo. Macrophages (green) are concentrated in areas of cell death, blood vessels (red) are labelled with SNA lectin. (C) ACTN line embryo spinal cord stage 16 HH. (D) Dorsal Root Ganglion of the nervous system of a Chameleon transgenic chicken embryo. Nerves going into the dorsal root ganglion are red, and nerves coming out are green. (E) Fluorescent image of the dorsal skin (periderm) from a membrane GFP chick embryo. (F) FUCHI cell cycle reporter embryo stage 23 HH. All images were provided by members of The Roslin Institute Chicken Embryology (RICE) group.

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Developmental Biology @devbiol.bsky.social · 6d

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New tools bring embryonic feather bud development back to the forefront of efforts to understand vertebrate organogenesis

By Jon Riddell and Denis Headon

tinyurl.com/hzzhr5z8
#SpecialIssue on #Development and #Regeneration of ectodermal organs

(A) Schematic of embryonic chick skin, composed of an epithelial layer overlying a mesenchyme containing cells migrating within an extracellular matrix. During early stages of feather development dermal fibroblasts aggregate underneath epithelial thickenings, known as placodes, to form dermal condensates. (B) Skin explant dissected from an embryonic day 9 (E9) tdTomato transgenic embryo showing feather buds growing out and oriented towards the posterior. Scale bar 1 mm. (C) Dermal condensates form in sequential rows, originating from a dense mesenchymal stripe along the midline of the embryo. This stripe then separates into condensates, with subsequent rows emerging laterally in sequence. (D) In situ hybridisation detecting CTNNB1 expression in E8 chick skin. The red outline highlights the hexagonal arrangement of the 6 nearest-neighbour feather buds. (E) Haematoxylin and eosin stain of an E6.5 chick embryo section. The red dashed rectangle highlights the loose dermis, the green dashed rectangle highlights the dense dermis. Left panel scale bar = 200 μm, right panel scale bars = 100 μm.

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Developmental Biology @devbiol.bsky.social · 7d

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Gpnmb promotes the recruitment of macrophages post cardiac cryoinjury in zebrafish, influencing immune and fibrotic responses during regeneration

-S Gupta, GK Bajwa, H El-Sammak, K Mattonet, S Günther, M Looso, D Stainier, R Marín-Juez @rmarinjuez.bsky.social

tinyurl.com/yc7hv5dn

Upper panel: Immunostaining of zebrafish ventricles at 7 dpci after cryoinjury shows fewer macrophages (mpeg1:EGFP⁺, magenta) in gpnmb⁻/⁻ ventricles compared with wild-type. DAPI staining (blue) marks nuclei (B). Quantification confirms a significant reduction in macrophage numbers within the injured border zone of gpnmb⁻/⁻ tissue (C).

Lower panel: Acid Fuchsin Orange-G (AFOG) stained sections of zebrafish cryoinjured ventricles show that gpnmb⁻/⁻ ventricles develop larger collagen-rich scars than wild-type at 30 and 90 dpci (F and G). Quantification illustrates greater proportions of large scar areas in gpnmb⁻/⁻ ventricles (H), indicating impaired scar resolution and delayed cardiac regeneration.

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Developmental Biology @devbiol.bsky.social · 8d

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CMTM4 is an adhesion modulator that regulates skeletal patterning and primary mesenchyme cell migration in sea urchin embryos

By Abigail Descoteaux, Marko Radulovic, Dona Alburi, and Cynthia Bradham

tinyurl.com/3xvnzxuz

Microscopy images of 48hpf sea urchin embryos as skeletal birefringence images; insets show morphology of the corresponding embryo in brightfield. Control (A), CMTM4 MO-injected (B), CMTM4 mRNA-injected (C), and CMTM4 MO and mRNA co-injected (D) embryos.

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Developmental Biology @devbiol.bsky.social · 8d

Full paper link: tinyurl.com/vcp23d95

Exploring the differentiation potential of EomesPOS mouse trophoblast cells in mid-gestation

Mouse trophoblast stem (mTS) cells can be derived from the blastocyst or extraembryonic ectoderm as late as embryonic day (E) 6.5 and when cultured in…

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Developmental Biology @devbiol.bsky.social · 8d

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Lineage tracing of Eomes-positive mouse trophoblast cells confirms their capacity to contribute to both placental layers in vivo even after E7.5

-Avery McGinnis, Megan Cull, Nichole Peterson, Matthew Tang, Bryony Natale @bnatale.bsky.social, David Natale

#Extraembryonic

Immunofluorescence Staining of E17.5 Ai6 x Eomes-Cre Placentae for Mesenchymal Cells. EomesPOS cells and daughters (ZsGreen; green), all counterstained with NucBlue (DAPI; blue). (A) Staining of endothelial cells in the chorion and lower labyrinth layer with an anti-CD31 antibody (red; 400x). Ai6NEG (above) and Ai6POS (below). (B) Staining of placental pericytes in the labyrinth layer with an anti-αSMA antibody (red; 400x). Ai6NEG (above) and Ai6POS (below). White arrowheads show colocalization of ZsGreen with antibody staining.

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Developmental Biology @devbiol.bsky.social · 9d

Full paper link: tinyurl.com/yc3p496h

Midkine-a interacts with Ptprz1b to regulate neural plate convergence and midline formation in the developing zebrafish hindbrain

A midline in the developing central nervous system allows symmetric distribution of neural progenitors that later establish functional, bilaterally sy…

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Developmental Biology @devbiol.bsky.social · 9d

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Growth factor Mdka interacts with Ptprz1b to regulate midline formation in the developing zebrafish hindbrain by controlling the levels of prickle expression

By Y Le, K Rajasekhar, T Loo, T Saunders @timesaunders.bsky.social T Wohland, C Winkler

#Zebrafish #Neurodevelopment

Expression and interaction of zebrafish Mdka, Mdkb and Ptn with Ptprz1b.
(A) Hybridization chain reaction RNA in situ hybridization (HCR) of mdka, mdkb and ptn expression in wildtype embryos at 10 hpf (neural plate stage) and 12 hpf (early neural keel stage). Scale bars = 50 μm.
(B) Fluorescent RNA in situ hybridization (FISH) of mdka, mdkb and ptn expression in wildtype embryos at 14 hpf. Left: Schematic diagram of hindbrain organization, dorsal view with dashed box indicating rhombomere region (r1 to r6) analyzed by FISH. NC = negative control (mdka sense probe). Dorsal views and pseudo-colored. Scale bars = 50 μm.
(C) Mean fluorescent intensity of FISH signals in (B) along anteroposterior axis of r1 to r6.
(D) Images after proximity ligation assay (PLA) of controls and different pairs of ligands (Mdka, Mdkb, Ptn) and receptor (Ptprz1b). Embryos injected with HA-ptprz1b mRNA alone served as the negative control (NC). Positive controls (PC) are mdka-MYC mRNA-injected embryos using two pairing secondary antibodies that recognize the same primary antibody. Embryos co-injected with mdka-MYC and secreted EGFP (secEGFP) mRNA served as random collision controls. PLA signals are represented in cyan, and DAPI in magenta. Scale bars = 20 μm.
(E) Statistical analysis of PLA levels normalized to DAPI signals after thresholding (PLA/DAPI area ratios). Data are presented as scattered dots with mean ± SD.
(F) Representative super resolution single plane images of PLA signals from Mdka-MYC/Mdkb-MYC/Ptn-MYC and mEGFP-Ptprz1b, respectively. mEGFP-Ptprz1b is colored in cyan, PLA in magenta, and DAPI in gray. PLA signals on plasma membrane are indicated by yellow arrowheads. Scale bars = 20 μm.

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Developmental Biology @devbiol.bsky.social · 10d

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Novel Gem3-NAT1 genetic interaction drives neuromuscular development in Drosophila without physical contact

By Rebecca Cacciottolo and Ruben Cauchi

tinyurl.com/5bp2jftd
#Drosophila #Neurodevelopment

Lollipop plots presenting significant biological process terms enriched in downregulated and unregulated DEGs upon gene ontology (GO) analysis. Overlapping downregulated pathways downstream of Gem3 and NAT1 RNAi include those associated with general organism development, particularly neurodevelopment and imaginal disc development. Common upregulated pathways in response to knockdown of Gem3 and NAT1 include several associated with metabolic processes revolving around small molecules, carboxylic acids, oxoacids as well as the generation of precursor metabolites and energy. GO terms are sorted by FDR (<0.05) with the colour of the lollipops representing the values of the enrichment analysis relative to the other displayed terms (brighter red is more significant) and the size of the dots represent the number of genes that comprise the term. GO terms that are colour-coded and tagged with a star indicate pathway overlap across the Gem3 and NAT1 RNA-seq datasets.

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Developmental Biology @devbiol.bsky.social · 11d

There are no large-scale defects detectable with anti-HRP in the axon scaffold.
In homozygous slit2 null mutants, all axons collapse at the midline due to a complete lack of midline repulsion, but Robo3 protein is still localized properly to axons.

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Developmental Biology @devbiol.bsky.social · 11d

Lower images show anti-Robo3 channel alone from the same embryos. In wild type embryos, endogenous Robo3 protein is detectable on longitudinal axons within the outer two-thirds of the neuropile. Robo3 protein is undetectable in embryos homozygous for the robo3 loss of function and deletion alleles.

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Developmental Biology @devbiol.bsky.social · 11d

Apologies for the missing Alt text
Fluorescent microscopy images of stage 16–17 Drosophila embryonic ventral nerve cords form wild type, mutant, and modified robo3 alleles, stained with anti-HRP (magenta; labels all axons) and anti-Robo3 (green) antibodies.

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Developmental Biology @devbiol.bsky.social · 11d

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Slit-independent guidance of longitudinal axons by Drosophila Robo3

"A non-Slit-binding function of Robo3 Ig1 contributes to its axon guidance activity."

by Abigail Carranza, Timothy Evans et al
@timevansphd.bsky.social

sciencedirect.com/science/arti...

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Developmental Biology @devbiol.bsky.social · 15d

Full Paper Link: tinyurl.com/56u55wxs

Guiding students to think critically about reproductive development and public conversations on sex and gender

Developmental Biology is intricately connected to current issues of societal and political importance. Bringing these connections into the classroom m…

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Developmental Biology @devbiol.bsky.social · 15d

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Connecting developmental biology to societal and political issues in the classroom boosts student engagement and critical thinking, fostering a deeper understanding of both science and social justice.
- Megan Morgan Hoffman
#SpecialIssue on teaching #DevelopmentalBiology for #SocialChange

Hand written notes on the developmental cascade leading to ovaries, testis, and their hormonal and genetic interconnections

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Developmental Biology @devbiol.bsky.social · 18d

By Melissa Marks and Emma Coddington Brown
#SpecialIssue on teaching #DevelopmentalBiology for #SocialChange

Mammalian lactation as a framework for teaching development, physiology, and cell biology for social change

Mammalian lactation is a dynamic process that develops throughout the lifespan of an organism. Here we present a framework for a third semester core c…

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Developmental Biology @devbiol.bsky.social · 18d

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Mammalian lactation as a dynamic theme to teach core biological concepts while integrating social and economic contexts, fostering not only scientific knowledge but also socially responsible thinking through high-impact, student-centred learning practices.

tinyurl.com/ydj8ujuy

Circular diagram representing the modular structure for a core biology course that centres lactation. At the centre is a woman nursing a child captioned "core biology course". Module 1 in red "Foundations" depicts colourful human stick figures. Module 2 in yellow "Anatomy" show an anatomical reddening of a lactating breast. Module 3 in green "Sociobiology" shows a translation sign. Module 4 in blue "cell biology" shows a mammary cell producing milk. Module 5 in purple "integration systems" delves into the neuroendocrine regulation of milk synthesis and secretion.

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Developmental Biology @devbiol.bsky.social · 18d

By Melissa marks and Emma Coddington Brown
#SpecialIssue on teaching #DevelopmentalBiology for #SocialChange

Mammalian lactation as a framework for teaching development, physiology, and cell biology for social change

Mammalian lactation is a dynamic process that develops throughout the lifespan of an organism. Here we present a framework for a third semester core c…

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Developmental Biology @devbiol.bsky.social · 19d

By Jonathan Slack

tinyurl.com/3w27mztf

“Pattern regulation in epimorphic fields”, aka the polar coordinate model

The Polar Coordinate Model (PCM) was a model, published in 1976, to account for the properties of distal regeneration in the appendages of insects and…

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Developmental Biology @devbiol.bsky.social · 19d

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Origins, findings, challenges, and influence of the Polar Coordinate Model, which revolutionized understanding of limb regeneration by framing pattern formation as positional information encoded in coordinate ‘maps’ across tissues.

#SpecialIssue on #Oogenesis in animals and plants

Diagram captioned "Rules of regeneration". Centre, a polar coordinate system; bottom left, a Drosophila wing imaginal disc; bottom right, a tetrapod limb; upper right, an insect limb.

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