TY  - JOUR
AB  - Organs that pump luminal fluids by the coordinated beat of motile cilia are integral to animal physiology. Such organs include the human airways, brain ventricles and reproductive tracts. Although cilia organization and duct morphology vary drastically in the animal kingdom, ducts are typically classified as carpet or flame designs. The reason behind the appearance of these two different designs and how they relate to fluid pumping remain unclear. Here, we demonstrate that two structural parameters—lumen diameter and cilia-to-lumen ratio—organize the observed duct diversity into a continuous spectrum that connects carpets to flames across all animal phyla. Using a unified fluid model, we show that carpets and flames represent trade-offs between flow rate and pressure generation. We propose that the convergence of ciliated organ designs follows functional constraints rather than phylogenetic distance and offer guiding design principles for synthetic ciliary pumps.
AU  - Ling, F.
AU  - Essock-Burns, T.*
AU  - McFall-Ngai, M.*
AU  - Katija, K.*
AU  - Nawroth, J.
AU  - Kanso, E.*
C1  - 71420
C2  - 56110
CY  - Heidelberger Platz 3, Berlin, 14197, Germany
SP  - 1679-1686
TI  - Flow physics guides morphology of ciliated organs.
JO  - Nat. Phys.
VL  - 20
IS  - 10
PB  - Nature Portfolio
PY  - 2024
SN  - 1745-2473
ER  - 

TY  - JOUR
AB  - Organ development involves complex shape transformations driven by active mechanical stresses that sculpt the growing tissue1,2. Epithelial gland morphogenesis is a prominent example where cylindrical branches transform into spherical alveoli during growth3–5. Here we show that this shape transformation is induced by a local change from anisotropic to isotropic tension within the epithelial cell layer of developing human mammary gland organoids. By combining laser ablation with optical force inference and theoretical analysis, we demonstrate that circumferential tension increases at the expense of axial tension through a reorientation of cells that correlates with the onset of persistent collective rotation around the branch axis. This enables the tissue to locally control the onset of a generalized Rayleigh–Plateau instability, leading to spherical tissue buds6. The interplay between cell motion, cell orientation and tissue tension is a generic principle that may turn out to drive shape transformations in other cell tissues.
AU  - Fernández, P.A.*
AU  - Buchmann, B.*
AU  - Goychuk, A.*
AU  - Engelbrecht, L.K.
AU  - Raich, M.K.*
AU  - Scheel, C.
AU  - Frey, E.*
AU  - Bausch, A.R.*
C1  - 63245
C2  - 51395
CY  - Heidelberger Platz 3, Berlin, 14197, Germany
SP  - 1130-1136
TI  - Surface-tension-induced budding drives alveologenesis in human mammary gland organoids.
JO  - Nat. Phys.
VL  - 17
IS  - 10
PB  - Nature Portfolio
PY  - 2021
SN  - 1745-2473
ER  - 

TY  - JOUR
AU  - Müller, J.
AU  - Kretzschmar, M.*
C1  - 61527
C2  - 50327
CY  - Heidelberger Platz 3, Berlin, 14197, Germany
SP  - 555–556
TI  - Forward thinking on backward tracing.
JO  - Nat. Phys.
VL  - 17
PB  - Nature Research
PY  - 2021
SN  - 1745-2473
ER  -