Daniel T Grimes | Princeton University (original) (raw)
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Papers by Daniel T Grimes
Developmental Biology, 2011
serves in part to buffer melanogaster against environmental variation to ensure robustness of D/V... more serves in part to buffer melanogaster against environmental variation to ensure robustness of D/V patterning.
Mechanisms of Development, 2009
Interneurons constitute most of the neurons in the vertebrate nervous system and they function in... more Interneurons constitute most of the neurons in the vertebrate nervous system and they function in almost all neural circuits and behaviours. However, our knowledge about how different types of interneurons develop is still very limited. Zebrafish
Human Molecular Genetics, 2009
The mammalian Sonic hedgehog (Shh) signalling pathway is essential for embryonic development and ... more The mammalian Sonic hedgehog (Shh) signalling pathway is essential for embryonic development and the patterning of multiple organs. Disruption or activation of Shh signalling leads to multiple birth defects, including holoprosencephaly, neural tube defects and polydactyly, and in adults results in tumours of the skin or central nervous system. Genetic approaches with model organisms continue to identify novel components of the pathway, including key molecules that function as positive or negative regulators of Shh signalling. Data presented here define Tulp3 as a novel negative regulator of the Shh pathway. We have identified a new mouse mutant that is a strongly hypomorphic allele of Tulp3 and which exhibits expansion of ventral markers in the caudal spinal cord, as well as neural tube defects and preaxial polydactyly, consistent with increased Shh signalling. We demonstrate that Tulp3 acts genetically downstream of Shh and Smoothened (Smo) in neural tube patterning and exhibits a genetic interaction with Gli3 in limb development. We show that Tulp3 does not appear to alter expression or processing of Gli3, and we demonstrate that transcriptional regulation of other negative regulators (Rab23, Fkbp8, Thm1, Sufu and PKA) is not affected. We discuss the possible mechanism of action of Tulp3 in Shh-mediated signalling in light of these new data.
During mammalian development, left-right (L-R) asymmetry is established by a cilia-driven left-wa... more During mammalian development, left-right (L-R) asymmetry is established by a cilia-driven left-ward fluid flow within a midline embryonic cavity called the node. This 'nodal flow' is detected by peripherally-located crown cells that each assemble a primary cilium which contain the putative Ca 2+ channel PKD2. The interaction of flow and crown cell cilia promotes left side-specific expression of Nodal in the lateral plate mesoderm (LPM). Whilst the PKD2-interacting protein PKD1L1 has also been implicated in L-R patterning, the underlying mechanism by which flow is detected and the genetic relationship between Polycystin function and asymmet-ric gene expression remains unknown. Here, we characterize a Pkd1l1 mutant line in which Nodal is activated bilaterally, suggesting that PKD1L1 is not required for LPM Nodal pathway activation per se, but rather to restrict Nodal to the left side downstream of nodal flow. Epistasis analysis shows that Pkd1l1 acts as an upstream genetic repressor of Pkd2. This study therefore provides a genetic pathway for the early stages of L-R determination. Moreover, using a system in which cultured cells are supplied artificial flow, we demonstrate that PKD1L1 is sufficient to mediate a Ca 2+ signaling response after flow stimulation. Finally, we show that an extracellular PKD domain within PKD1L1 is crucial for PKD1L1 function; as such, destabilizing the domain causes L-R defects in the mouse. Our demonstration that PKD1L1 protein can mediate a response to flow coheres with a mechanosensation model of flow sensation in which the force of fluid flow drives asymmetric gene expression in the embryo.
kurly (kur) mutants exhibit defects characteristic of motile cilia dysfunction c21orf59 is mutat... more kurly (kur) mutants exhibit defects characteristic of motile cilia
dysfunction c21orf59 is mutated in kur and is needed for dynein arm localization/cilia motility
CRISPR/Cas9 with homologous recombination in Xenopus shows C21orf59 regulates PCP
C21orf59 interacts with various PCP components to correctly polarize motile cilia
Initially identified in DNA damage repair, ATM-interactor (ATMIN) further functions as a transcri... more Initially identified in DNA damage repair, ATM-interactor (ATMIN) further functions as a transcriptional regulator of lung morphogenesis. Here we analyse three mouse mutants, Atmin gpg6/gpg6 , Atmin H210Q/H210Q and Dynll1 GT/GT , revealing how ATMIN and its transcriptional target dynein light chain LC8-type 1 (DYNLL1) are required for normal lung morphogenesis and ciliogenesis. Expression screening of ciliogenic genes confirmed Dynll1 to be controlled by ATMIN and further revealed moderately altered expression of known intraflagellar transport (IFT) protein-encoding loci in Atmin mutant embryos. Significantly, Dynll1 GT/GT embryonic cilia exhibited shortening and bulging, highly similar to the characterised retrograde IFT phenotype of Dync2h1. Depletion of ATMIN or DYNLL1 in cultured cells recapitulated the in vivo ciliogenesis phenotypes and expression of DYNLL1 or the related DYNLL2 rescued the effects of loss of ATMIN, demonstrating that ATMIN primarily promotes ciliogenesis by regulating Dynll1 expression. Furthermore, DYNLL1 as well as DYNLL2 localised to cilia in puncta, consistent with IFT particles, and physically interacted with WDR34, a mammalian homologue of the Chlamydomonas cytoplasmic dynein 2 intermediate chain that also localised to the cilium. This study extends the established Atmin-Dynll1 relationship into a developmental and a ciliary context, uncovering a novel series of interactions between DYNLL1, WDR34 and ATMIN. This identifies potential novel components of cytoplasmic dynein 2 and furthermore provides fresh insights into the molecular pathogenesis of human skeletal ciliopathies.
Although the human body shows left-right (L-R) mirror symmetry when viewed externally, the placem... more Although the human body shows left-right (L-R) mirror symmetry when viewed externally, the placement and patterning of the internal organs and associated vasculature are strikingly asymmetrical. In the mammalian early embryo, L-R symmetry is broken by the action of rotating cilia—small hair-like protrusions on the surface of cells—in a pit-like structure called the node (see the figure).These cilia generate a unidirectional flow of fluid across the node from right to left (1). This nodal flow breaks L-R symmetry by driving asymmetries in gene expression and Ca2+ signaling in cells at the periphery of the node. On page 226 of this issue, Yoshiba et al. (2) reveal a mechanism by which the mouse embryo senses nodal flow.
"The ciliopathies are an apparently disparate group of human diseases that all result from defect... more "The ciliopathies are an apparently disparate group of human diseases that all result from defects in the formation
and/or function of cilia. They include disorders such as Meckel-Grüber syndrome (MKS), Joubert syndrome (JBTS),
Bardet-Biedl syndrome (BBS) and Alström syndrome (ALS). Reflecting the manifold requirements for cilia in signalling,
sensation and motility, different ciliopathies exhibit common elements. The mouse has been used widely as a model
organism for the study of ciliopathies. Although many mutant alleles have proved lethal, continued investigations have
led to the development of better models. Here, we review current mouse models of a core set of ciliopathies, their
utility and future prospects."
In mammals, left-right (L-R) asymmetry is established by posteriorly oriented cilia driving a lef... more In mammals, left-right (L-R) asymmetry is established by posteriorly oriented cilia driving a leftwards laminar flow in the embryonic node, thereby activating asymmetric gene expression. The two-cilia hypothesis argues that immotile cilia detect and respond to this flow through a Pkd2-mediated mechanism; a putative sensory partner protein has, however, remained unidentified. We have identified the Pkd1-related locus Pkd1l1 as a crucial component of L-R patterning in mouse. Systematic comparison of Pkd1l1 and Pkd2 point mutants reveals strong phenocopying, evidenced by both morphological and molecular markers of sidedness; both mutants fail to activate asymmetric gene expression at the node or in the lateral plate and exhibit right isomerism of the lungs. Node and cilia morphology were normal in mutants and cilia demonstrated typical motility, consistent with Pkd1l1 and Pkd2 activity downstream of nodal flow. Cell biological analysis reveals that Pkd1l1 and Pkd2 localise to the cilium and biochemical experiments demonstrate that they can physically interact. Together with co-expression in the node, these data argue that Pkd1l1 is the elusive Pkd2 binding partner required for L-R patterning and support the two-cilia hypothesis.
The mammalian Sonic hedgehog (Shh) signalling pathway is essential for embryonic development and ... more The mammalian Sonic hedgehog (Shh) signalling pathway is essential for embryonic development and the patterning of multiple organs. Disruption or activation of Shh signalling leads to multiple birth defects, including holoprosencephaly, neural tube defects and polydactyly, and in adults results in tumours of the skin or central nervous system. Genetic approaches with model organisms continue to identify novel components of the pathway, including key molecules that function as positive or negative regulators of Shh signalling. Data presented here define Tulp3 as a novel negative regulator of the Shh pathway. We have identified a new mouse mutant that is a strongly hypomorphic allele of Tulp3 and which exhibits expansion of ventral markers in the caudal spinal cord, as well as neural tube defects and preaxial polydactyly, consistent with increased Shh signalling. We demonstrate that Tulp3 acts genetically downstream of Shh and Smoothened (Smo) in neural tube patterning and exhibits a genetic interaction with Gli3 in limb development. We show that Tulp3 does not appear to alter expression or processing of Gli3, and we demonstrate that transcriptional regulation of other negative regulators (Rab23, Fkbp8, Thm1, Sufu and PKA) is not affected. We discuss the possible mechanism of action of Tulp3 in Shh-mediated signalling in light of these new data.
Developmental Biology, 2011
serves in part to buffer melanogaster against environmental variation to ensure robustness of D/V... more serves in part to buffer melanogaster against environmental variation to ensure robustness of D/V patterning.
Mechanisms of Development, 2009
Interneurons constitute most of the neurons in the vertebrate nervous system and they function in... more Interneurons constitute most of the neurons in the vertebrate nervous system and they function in almost all neural circuits and behaviours. However, our knowledge about how different types of interneurons develop is still very limited. Zebrafish
Human Molecular Genetics, 2009
The mammalian Sonic hedgehog (Shh) signalling pathway is essential for embryonic development and ... more The mammalian Sonic hedgehog (Shh) signalling pathway is essential for embryonic development and the patterning of multiple organs. Disruption or activation of Shh signalling leads to multiple birth defects, including holoprosencephaly, neural tube defects and polydactyly, and in adults results in tumours of the skin or central nervous system. Genetic approaches with model organisms continue to identify novel components of the pathway, including key molecules that function as positive or negative regulators of Shh signalling. Data presented here define Tulp3 as a novel negative regulator of the Shh pathway. We have identified a new mouse mutant that is a strongly hypomorphic allele of Tulp3 and which exhibits expansion of ventral markers in the caudal spinal cord, as well as neural tube defects and preaxial polydactyly, consistent with increased Shh signalling. We demonstrate that Tulp3 acts genetically downstream of Shh and Smoothened (Smo) in neural tube patterning and exhibits a genetic interaction with Gli3 in limb development. We show that Tulp3 does not appear to alter expression or processing of Gli3, and we demonstrate that transcriptional regulation of other negative regulators (Rab23, Fkbp8, Thm1, Sufu and PKA) is not affected. We discuss the possible mechanism of action of Tulp3 in Shh-mediated signalling in light of these new data.
During mammalian development, left-right (L-R) asymmetry is established by a cilia-driven left-wa... more During mammalian development, left-right (L-R) asymmetry is established by a cilia-driven left-ward fluid flow within a midline embryonic cavity called the node. This 'nodal flow' is detected by peripherally-located crown cells that each assemble a primary cilium which contain the putative Ca 2+ channel PKD2. The interaction of flow and crown cell cilia promotes left side-specific expression of Nodal in the lateral plate mesoderm (LPM). Whilst the PKD2-interacting protein PKD1L1 has also been implicated in L-R patterning, the underlying mechanism by which flow is detected and the genetic relationship between Polycystin function and asymmet-ric gene expression remains unknown. Here, we characterize a Pkd1l1 mutant line in which Nodal is activated bilaterally, suggesting that PKD1L1 is not required for LPM Nodal pathway activation per se, but rather to restrict Nodal to the left side downstream of nodal flow. Epistasis analysis shows that Pkd1l1 acts as an upstream genetic repressor of Pkd2. This study therefore provides a genetic pathway for the early stages of L-R determination. Moreover, using a system in which cultured cells are supplied artificial flow, we demonstrate that PKD1L1 is sufficient to mediate a Ca 2+ signaling response after flow stimulation. Finally, we show that an extracellular PKD domain within PKD1L1 is crucial for PKD1L1 function; as such, destabilizing the domain causes L-R defects in the mouse. Our demonstration that PKD1L1 protein can mediate a response to flow coheres with a mechanosensation model of flow sensation in which the force of fluid flow drives asymmetric gene expression in the embryo.
kurly (kur) mutants exhibit defects characteristic of motile cilia dysfunction c21orf59 is mutat... more kurly (kur) mutants exhibit defects characteristic of motile cilia
dysfunction c21orf59 is mutated in kur and is needed for dynein arm localization/cilia motility
CRISPR/Cas9 with homologous recombination in Xenopus shows C21orf59 regulates PCP
C21orf59 interacts with various PCP components to correctly polarize motile cilia
Initially identified in DNA damage repair, ATM-interactor (ATMIN) further functions as a transcri... more Initially identified in DNA damage repair, ATM-interactor (ATMIN) further functions as a transcriptional regulator of lung morphogenesis. Here we analyse three mouse mutants, Atmin gpg6/gpg6 , Atmin H210Q/H210Q and Dynll1 GT/GT , revealing how ATMIN and its transcriptional target dynein light chain LC8-type 1 (DYNLL1) are required for normal lung morphogenesis and ciliogenesis. Expression screening of ciliogenic genes confirmed Dynll1 to be controlled by ATMIN and further revealed moderately altered expression of known intraflagellar transport (IFT) protein-encoding loci in Atmin mutant embryos. Significantly, Dynll1 GT/GT embryonic cilia exhibited shortening and bulging, highly similar to the characterised retrograde IFT phenotype of Dync2h1. Depletion of ATMIN or DYNLL1 in cultured cells recapitulated the in vivo ciliogenesis phenotypes and expression of DYNLL1 or the related DYNLL2 rescued the effects of loss of ATMIN, demonstrating that ATMIN primarily promotes ciliogenesis by regulating Dynll1 expression. Furthermore, DYNLL1 as well as DYNLL2 localised to cilia in puncta, consistent with IFT particles, and physically interacted with WDR34, a mammalian homologue of the Chlamydomonas cytoplasmic dynein 2 intermediate chain that also localised to the cilium. This study extends the established Atmin-Dynll1 relationship into a developmental and a ciliary context, uncovering a novel series of interactions between DYNLL1, WDR34 and ATMIN. This identifies potential novel components of cytoplasmic dynein 2 and furthermore provides fresh insights into the molecular pathogenesis of human skeletal ciliopathies.
Although the human body shows left-right (L-R) mirror symmetry when viewed externally, the placem... more Although the human body shows left-right (L-R) mirror symmetry when viewed externally, the placement and patterning of the internal organs and associated vasculature are strikingly asymmetrical. In the mammalian early embryo, L-R symmetry is broken by the action of rotating cilia—small hair-like protrusions on the surface of cells—in a pit-like structure called the node (see the figure).These cilia generate a unidirectional flow of fluid across the node from right to left (1). This nodal flow breaks L-R symmetry by driving asymmetries in gene expression and Ca2+ signaling in cells at the periphery of the node. On page 226 of this issue, Yoshiba et al. (2) reveal a mechanism by which the mouse embryo senses nodal flow.
"The ciliopathies are an apparently disparate group of human diseases that all result from defect... more "The ciliopathies are an apparently disparate group of human diseases that all result from defects in the formation
and/or function of cilia. They include disorders such as Meckel-Grüber syndrome (MKS), Joubert syndrome (JBTS),
Bardet-Biedl syndrome (BBS) and Alström syndrome (ALS). Reflecting the manifold requirements for cilia in signalling,
sensation and motility, different ciliopathies exhibit common elements. The mouse has been used widely as a model
organism for the study of ciliopathies. Although many mutant alleles have proved lethal, continued investigations have
led to the development of better models. Here, we review current mouse models of a core set of ciliopathies, their
utility and future prospects."
In mammals, left-right (L-R) asymmetry is established by posteriorly oriented cilia driving a lef... more In mammals, left-right (L-R) asymmetry is established by posteriorly oriented cilia driving a leftwards laminar flow in the embryonic node, thereby activating asymmetric gene expression. The two-cilia hypothesis argues that immotile cilia detect and respond to this flow through a Pkd2-mediated mechanism; a putative sensory partner protein has, however, remained unidentified. We have identified the Pkd1-related locus Pkd1l1 as a crucial component of L-R patterning in mouse. Systematic comparison of Pkd1l1 and Pkd2 point mutants reveals strong phenocopying, evidenced by both morphological and molecular markers of sidedness; both mutants fail to activate asymmetric gene expression at the node or in the lateral plate and exhibit right isomerism of the lungs. Node and cilia morphology were normal in mutants and cilia demonstrated typical motility, consistent with Pkd1l1 and Pkd2 activity downstream of nodal flow. Cell biological analysis reveals that Pkd1l1 and Pkd2 localise to the cilium and biochemical experiments demonstrate that they can physically interact. Together with co-expression in the node, these data argue that Pkd1l1 is the elusive Pkd2 binding partner required for L-R patterning and support the two-cilia hypothesis.
The mammalian Sonic hedgehog (Shh) signalling pathway is essential for embryonic development and ... more The mammalian Sonic hedgehog (Shh) signalling pathway is essential for embryonic development and the patterning of multiple organs. Disruption or activation of Shh signalling leads to multiple birth defects, including holoprosencephaly, neural tube defects and polydactyly, and in adults results in tumours of the skin or central nervous system. Genetic approaches with model organisms continue to identify novel components of the pathway, including key molecules that function as positive or negative regulators of Shh signalling. Data presented here define Tulp3 as a novel negative regulator of the Shh pathway. We have identified a new mouse mutant that is a strongly hypomorphic allele of Tulp3 and which exhibits expansion of ventral markers in the caudal spinal cord, as well as neural tube defects and preaxial polydactyly, consistent with increased Shh signalling. We demonstrate that Tulp3 acts genetically downstream of Shh and Smoothened (Smo) in neural tube patterning and exhibits a genetic interaction with Gli3 in limb development. We show that Tulp3 does not appear to alter expression or processing of Gli3, and we demonstrate that transcriptional regulation of other negative regulators (Rab23, Fkbp8, Thm1, Sufu and PKA) is not affected. We discuss the possible mechanism of action of Tulp3 in Shh-mediated signalling in light of these new data.