Publications by authors named "Allan K Mah"
Article Synopsis
- The POU transcription factor CEH-6 is necessary for regulating the expression of the aqp-8 gene in the excretory cell of C. elegans, which functions similarly to a kidney, by binding to a specific octamer sequence in the gene's promoter.
- Research identified important positional requirements for the octamer and discovered 165 conserved genes across C. elegans species that have functional octamers, indicating a strong link between these sequences and gene expression in the excretory cell.
- By analyzing the effects of mutations in the octamer and its surrounding sequences, the study shows that modifying these regions can significantly alter gene expression, thereby helping to find more genes involved in osmoregulation
The recent publication of the Caenorhabditis elegans cisRED database has provided an extensive catalog of upstream elements that are conserved between nematode genomes. We have performed a secondary analysis to determine which subsequences of the cisRED motifs are found in multiple locations throughout the C. elegans genome.
View Article and Find Full Text PDFLET-721 is the Caenorhabditis elegans ortholog of electron-transferring flavoprotein dehydrogenase (ETFDH). We are studying this protein in C. elegans in order to establish a tractable model system for further exploration of ETFDH structure and function.
View Article and Find Full Text PDFArticle Synopsis
- C. elegans was the first multicellular organism to have its genome fully sequenced, with the last gaps filled in 2002, providing a basis for studying segmental duplications.
- Researchers utilized a new tool called OrthoCluster to analyze the genome and identified 3,484 duplicated segments, termed duplicons, including a noteworthy 108 kb pair with 99.7% DNA identity.
- Genotyping revealed that only 29 out of 76 wild-type C. elegans strains possess this large duplication, indicating recent genomic changes.
Article Synopsis
- The nematode C. elegans relies on the aquaporin AQP-8 to regulate water balance in response to changing soil conditions, highlighting the importance of osmotic homeostasis.
- Promoter analysis identified a key regulatory region about 300 bp upstream of the aqp-8 gene, featuring an octamer motif crucial for the interaction with POU homeobox transcription factors.
- The study demonstrated that CEH-6, a specific POU protein expressed in C. elegans' excretory cells, regulates AQP-8 expression, paralleling the role of its mammalian counterpart, Brn1, in kidney gene expression, suggesting C. elegans could be a valuable model for studying kidney development in vertebrates.
The assembly and maintenance of cilia require intraflagellar transport (IFT), a microtubule-dependent bidirectional motility of multisubunit protein complexes along ciliary axonemes. Defects in IFT and the functions of motile or sensory cilia are associated with numerous human ailments, including polycystic kidney disease and Bardet-Biedl syndrome. Here, we identify a novel Caenorhabditis elegans IFT gene, IFT-associated gene 1 (ifta-1), which encodes a WD repeat-containing protein with strong homology to a mammalian protein of unknown function.
View Article and Find Full Text PDFArticle Synopsis
- The dpy-14 gene in Caenorhabditis elegans encodes an essential cuticular collagen, making it the earliest-expressing collagen known, starting at the 16 E cell stage during embryogenesis.
- Expression is primarily in ciliated neurons and hypodermal cells, indicating a collaboration between these cells for transcription and synthesis of DPY-14.
- Mutations in dpy-14 cause defects in amphid channel function and prevent proper fusion of seam cells, highlighting its crucial role in the worm's physiological development.
Cilia and flagella play important roles in many physiological processes, including cell and fluid movement, sensory perception, and development. The biogenesis and maintenance of cilia depend on intraflagellar transport (IFT), a motility process that operates bidirectionally along the ciliary axoneme. Disruption in IFT and cilia function causes several human disorders, including polycystic kidneys, retinal dystrophy, neurosensory impairment, and Bardet-Biedl syndrome (BBS).
View Article and Find Full Text PDFBardet-Biedl syndrome (BBS) is a genetically heterogeneous developmental disorder whose molecular basis is largely unknown. Here, we show that mutations in the Caenorhabditis elegans bbs-7 and bbs-8 genes cause structural and functional defects in cilia. C.
View Article and Find Full Text PDFBardet-Biedl syndrome (BBS) is a genetically heterogeneous disorder characterized primarily by retinal dystrophy, obesity, polydactyly, renal malformations and learning disabilities. Although five BBS genes have been cloned, the molecular basis of this syndrome remains elusive. Here we show that BBS is probably caused by a defect at the basal body of ciliated cells.
View Article and Find Full Text PDF