A key component of nervous system development is the migration of undifferentiated cells, termed neuroblasts, and their differentiation into neurons upon arrival at a target location. Mutations affecting the mechanisms responsible for neuroblast migration and localization can lead to numerous developmental defects. In humans, abnormal neuroblast migration results in structurally abnormal or missing areas of the brain in the cerebral hemispheres, cerebellum, brainstem, or hippocampus. Recently, we isolated a mutant strain of Caenorhabditis elegans exhibiting a Dumpy phenotype (short body length) and with aberrant localization of neurons that are derived from a neuroblast lineage known as the Q lineage. The mutation was renamed dpy-19(cnj1) once sequencing revealed that the mutation is a 12,495 bp deletion/12bp insertion affecting the dpy-19 gene. dpy-19 encodes a C-mannosyltransferase that glycosylates the tryptophan residues in thrombospondin repeats of cell surface receptors. While not all substrates of DPY-19 are known, one target is MIG-21, which requires glycosylation before its soluble form can be secreted during Q lineage migration. Previous studies have implicated dpy-19 in the initial polarization of Q neuroblasts (QL and QR) and in the direction of their migrations, however, these early studies were not performed using a true null allele of dpy-19 and did not have the benefit of fluorescent markers for live cell imaging. This motivated us to analyze the true null phenotype of dpy-19. While the dpy-19(cnj1) allele we isolated is predicted to completely remove dpy-19 function, it also results in a deletion of other genes. To eliminate the possibility that these other genes impact the phenotype, a true null allele, dpy-19(cnj5) was developed using CRISPR to study the neuronal and body length defects in detail. Firstly, we conducted a body length analysis comparing all available dpy-19 mutant strains to controls to determine the role of dpy-19 in animal length. Secondly, we scored the same mutants using GFP as a marker for Q-lineage neurons to determine how the loss of dpy-19 affects neuron positioning and migration. Lastly, we visualized QR and QL cells in L1 stage animals marked with GFP and screened for the direction of pseudopod growth to assess the impact of the loss of dpy-19 on the initial polarization of the neuroblasts. Our study confirms past studies, and also suggests that dpy-19 is important for the migration of the entire Q cell lineage. Four homologs of DPY-19 exist in humans, DPY19L1-4, suggesting conserved molecular function. DPY19L1 and DPY19L3 are also C-mannosyltransferases and are involved in radial migration of glutamatergic neurons in the developing cerebral cortex, and sperm head elongation and acrosome formation in sperm (Watanabe et al 2011.; Shang et al. 2019). The evolutionary conservation of dpy-19 across species indicates its function is imperative to the developing nervous system, and our research here illuminates how disruptions to its function can lead to multiple impaired phenotypes. A key component of nervous system development is the migration of undifferentiated cells, termed neuroblasts, and their differentiation into neurons upon arrival at a target location. Mutations affecting the mechanisms responsible for neuroblast migration and localization can lead to numerous developmental defects. In humans, abnormal neuroblast migration results in structurally abnormal or missing areas of the brain in the cerebral hemispheres, cerebellum, brainstem, or hippocampus. Recently, we isolated a mutant strain of Caenorhabditis elegans exhibiting a Dumpy phenotype (short body length) and with aberrant localization of neurons that are derived from a neuroblast lineage known as the Q lineage. The mutation was renamed dpy-19(cnj1) once sequencing revealed that the mutation is a 12,495 bp deletion/12bp insertion affecting the dpy-19 gene. dpy-19 encodes a C-mannosyltransferase that glycosylates the tryptophan residues in thrombospondin repeats of cell surface receptors. While not all substrates of DPY-19 are known, one target is MIG-21, which requires glycosylation before its soluble form can be secreted during Q lineage migration. Previous studies have implicated dpy-19 in the initial polarization of Q neuroblasts (QL and QR) and in the direction of their migrations, however, these early studies were not performed using a true null allele of dpy-19 and did not have the benefit of fluorescent markers for live cell imaging. This motivated us to analyze the true null phenotype of dpy-19. While the dpy-19(cnj1) allele we isolated is predicted to completely remove dpy-19 function, it also results in a deletion of other genes. To eliminate the possibility that these other genes impact the phenotype, a true null allele, dpy-19(cnj5) was developed using CRISPR to study the neuronal and body length defects in detail. Firstly, we conducted a body length analysis comparing all available dpy-19 mutant strains to controls to determine the role of dpy-19 in animal length. Secondly, we scored the same mutants using GFP as a marker for Q-lineage neurons to determine how the loss of dpy-19 affects neuron positioning and migration. Lastly, we visualized QR and QL cells in L1 stage animals marked with GFP and screened for the direction of pseudopod growth to assess the impact of the loss of dpy-19 on the initial polarization of the neuroblasts. Our study confirms past studies, and also suggests that dpy-19 is important for the migration of the entire Q cell lineage. Four homologs of DPY-19 exist in humans, DPY19L1-4, suggesting conserved molecular function. DPY19L1 and DPY19L3 are also C-mannosyltransferases and are involved in radial migration of glutamatergic neurons in the developing cerebral cortex, and sperm head elongation and acrosome formation in sperm (Watanabe et al 2011.; Shang et al. 2019). The evolutionary conservation of dpy-19 across species indicates its function is imperative to the developing nervous system, and our research here illuminates how disruptions to its function can lead to multiple impaired phenotypes. A key component of nervous system development is the migration of undifferentiated cells, termed neuroblasts, and their differentiation into neurons upon arrival at a target location. Mutations affecting the mechanisms responsible for neuroblast migration and localization can lead to numerous developmental defects. In humans, abnormal neuroblast migration results in structurally abnormal or missing areas of the brain in the cerebral hemispheres, cerebellum, brainstem, or hippocampus. Recently, we isolated a mutant strain of Caenorhabditis elegans exhibiting a Dumpy phenotype (short body length) and with aberrant localization of neurons that are derived from a neuroblast lineage known as the Q lineage. The mutation was renamed dpy-19(cnj1) once sequencing revealed that the mutation is a 12,495 bp deletion/12bp insertion affecting the dpy-19 gene. dpy-19 encodes a C-mannosyltransferase that glycosylates the tryptophan residues in thrombospondin repeats of cell surface receptors. While not all substrates of DPY-19 are known, one target is MIG-21, which requires glycosylation before its soluble form can be secreted during Q lineage migration. Previous studies have implicated dpy-19 in the initial polarization of Q neuroblasts (QL and QR) and in the direction of their migrations, however, these early studies were not performed using a true null allele of dpy-19 and did not have the benefit of fluorescent markers for live cell imaging. This motivated us to analyze the true null phenotype of dpy-19. While the dpy-19(cnj1) allele we isolated is predicted to completely remove dpy-19 function, it also results in a deletion of other genes. To eliminate the possibility that these other genes impact the phenotype, a true null allele, dpy-19(cnj5) was developed using CRISPR to study the neuronal and body length defects in detail. Firstly, we conducted a body length analysis comparing all available dpy-19 mutant strains to controls to determine the role of dpy-19 in animal length. Secondly, we scored the same mutants using GFP as a marker for Q-lineage neurons to determine how the loss of dpy-19 affects neuron positioning and migration. Lastly, we visualized QR and QL cells in L1 stage animals marked with GFP and screened for the direction of pseudopod growth to assess the impact of the loss of dpy-19 on the initial polarization of the neuroblasts. Our study confirms past studies, and also suggests that dpy-19 is important for the migration of the entire Q cell lineage. Four homologs of DPY-19 exist in humans, DPY19L1-4, suggesting conserved molecular function. DPY19L1 and DPY19L3 are also C-mannosyltransferases and are involved in radial migration of glutamatergic neurons in the developing cerebral cortex, and sperm head elongation and acrosome formation in sperm (Watanabe et al 2011.; Shang et al. 2019). The evolutionary conservation of dpy-19 across species indicates its function is imperative to the developing nervous system, and our research here illuminates how disruptions to its function can lead to multiple impaired phenotypes. A key component of nervous system development is the migration of undifferentiated cells, termed neuroblasts, and their differentiation into neurons upon arrival at a target location. Mutations affecting the mechanisms responsible for neuroblast migration and localization can lead to numerous developmental defects. In humans, abnormal neuroblast migration results in structurally abnormal or missing areas of the brain in the cerebral hemispheres, cerebellum, brainstem, or hippocampus. Recently, we isolated a mutant strain of Caenorhabditis elegans exhibiting a Dumpy phenotype (short body length) and with aberrant localization of neurons that are derived from a neuroblast lineage known as the Q lineage. The mutation was renamed dpy-19(cnj1) once sequencing revealed that the mutation is a 12,495 bp deletion/12bp insertion affecting the dpy-19 gene. dpy-19 encodes a C-mannosyltransferase that glycosylates the tryptophan residues in thrombospondin repeats of cell surface receptors. While not all substrates of DPY-19 are known, one target is MIG-21, which requires glycosylation before its soluble form can be secreted during Q lineage migration. Previous studies have implicated dpy-19 in the initial polarization of Q neuroblasts (QL and QR) and in the direction of their migrations, however, these early studies were not performed using a true null allele of dpy-19 and did not have the benefit of fluorescent markers for live cell imaging. This motivated us to analyze the true null phenotype of dpy-19. While the dpy-19(cnj1) allele we isolated is predicted to completely remove dpy-19 function, it also results in a deletion of other genes. To eliminate the possibility that these other genes impact the phenotype, a true null allele, dpy-19(cnj5) was developed using CRISPR to study the neuronal and body length defects in detail. Firstly, we conducted a body length analysis comparing all available dpy-19 mutant strains to controls to determine the role of dpy-19 in animal length. Secondly, we scored the same mutants using GFP as a marker for Q-lineage neurons to determine how the loss of dpy-19 affects neuron positioning and migration. Lastly, we visualized QR and QL cells in L1 stage animals marked with GFP and screened for the direction of pseudopod growth to assess the impact of the loss of dpy-19 on the initial polarization of the neuroblasts. Our study confirms past studies, and also suggests that dpy-19 is important for the migration of the entire Q cell lineage. Four homologs of DPY-19 exist in humans, DPY19L1-4, suggesting conserved molecular function. DPY19L1 and DPY19L3 are also C-mannosyltransferases and are involved in radial migration of glutamatergic neurons in the developing cerebral cortex, and sperm head elongation and acrosome formation in sperm (Watanabe et al 2011.; Shang et al. 2019). The evolutionary conservation of dpy-19 across species indicates its function is imperative to the developing nervous system, and our research here illuminates how disruptions to its function can lead to multiple impaired phenotypes. A key component of nervous system development is the migration of undifferentiated cells, termed neuroblasts, and their differentiation into neurons upon arrival at a target location. Mutations affecting the mechanisms responsible for neuroblast migration and localization can lead to numerous developmental defects. In humans, abnormal neuroblast migration results in structurally abnormal or missing areas of the brain in the cerebral hemispheres, cerebellum, brainstem, or hippocampus. Recently, we isolated a mutant strain of Caenorhabditis elegans exhibiting a Dumpy phenotype (short body length) and with aberrant localization of neurons that are derived from a neuroblast lineage known as the Q lineage. The mutation was renamed dpy-19(cnj1) once sequencing revealed that the mutation is a 12,495 bp deletion/12bp insertion affecting the dpy-19 gene. dpy-19 encodes a C-mannosyltransferase that glycosylates the tryptophan residues in thrombospondin repeats of cell surface receptors. While not all substrates of DPY-19 are known, one target is MIG-21, which requires glycosylation before its soluble form can be secreted during Q lineage migration. Previous studies have implicated dpy-19 in the initial polarization of Q neuroblasts (QL and QR) and in the direction of their migrations, however, these early studies were not performed using a true null allele of dpy-19 and did not have the benefit of fluorescent markers for live cell imaging. This motivated us to analyze the true null phenotype of dpy-19. While the dpy-19(cnj1) allele we isolated is predicted to completely remove dpy-19 function, it also results in a deletion of other genes. To eliminate the possibility that these other genes impact the phenotype, a true null allele, dpy-19(cnj5) was developed using CRISPR to study the neuronal and body length defects in detail. Firstly, we conducted a body length analysis comparing all available dpy-19 mutant strains to controls to determine the role of dpy-19 in animal length. Secondly, we scored the same mutants using GFP as a marker for Q-lineage neurons to determine how the loss of dpy-19 affects neuron positioning and migration. Lastly, we visualized QR and QL cells in L1 stage animals marked with GFP and screened for the direction of pseudopod growth to assess the impact of the loss of dpy-19 on the initial polarization of the neuroblasts. Our study confirms past studies, and also suggests that dpy-19 is important for the migration of the entire Q cell lineage. Four homologs of DPY-19 exist in humans, DPY19L1-4, suggesting conserved molecular function. DPY19L1 and DPY19L3 are also C-mannosyltransferases and are involved in radial migration of glutamatergic neurons in the developing cerebral cortex, and sperm head elongation and acrosome formation in sperm (Watanabe et al 2011.; Shang et al. 2019). The evolutionary conservation of dpy-19 across species indicates its function is imperative to the developing nervous system, and our research here illuminates how disruptions to its function can lead to multiple impaired phenotypes.