Zebrafish Anatomical Dictionary

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Structure description: lateral line

by Tanya Whitfield

Name: lateral line

Abbreviation:

pll (posterior lateral line)
all (anterior lateral line)
pllp (posterior lateral line primordium)
allp (anterior lateral line primordium)
pllg (posterior lateral line ganglion)
allg (anterior lateral line ganglion)
There are many other abbreviations for the individual lateral lines and nerve rami. See Raible and Kruse (2000) for a complete list.

Synonyms: None

Figures:

lateral line diagram placode

live neuromasts

neuromast polarity

Description: A sensory system on the surface of the fish, consisting of small sensory patches (neuromasts) distributed in discrete lines over the body surface. The lateral line system is stimulated by local water displacements and vibrations, and detects propulsion of the fish through the water, as well as facilitating shoaling, prey capture, and predator and obstacle avoidance. In the 4 day larva, there are eight distinct lateral lines (Raible and Kruse, 2000):

supraorbital (three neuromasts)
infraorbital (four neuromasts)
mandibular (two neuromasts)
opercular (one neuromast)
otic (superior and inferior rami; two neuromasts)
middle (superior and inferior rami; two neuromasts)
occipital (one neuromast)
posterior (dorsal and ventral rami; about 11 neuromasts)

The ventral ramus of the posterior line is the familiar "trunk" or "midbody" line, formed by the posterior lateral line primordium, the migration of which is used as a staging tool (Kimmel et al., 1995).Each neuromast consists of a rosette of hair cells and supporting cells, with their apical surfaces protruding through a circular hole in the periderm. The kinocilia and stereocilia of the hair cells are encased in a gelatinous cupula, visible in the live larva with DIC optics. Neuromast hair cells are arranged in one of two opposing polarities; in the trunk, these correspond to the anteroposterior axis of the body. Hair cells are innervated by lateral line nerves; cell bodies of afferent neurons sit in cranial anterior and posterior lateral line ganglia. Three types of efferent neurons have been described that project axons into the posterior lateral line nerve (Metcalfe et al., 1985).

Homologues:

• Human: none
• Mouse: none
• Chicken: none
• Frog: lateral line (present in larvae; also in adults of aquatic amphibia, such as Xenopus).
• Fly: none

Stages:

• First appears at: Posterior primordium first visible with DIC optics at 18-somite stage (18h).
• Disappears (or changes name) at: Posterior primordium reaches the end of the tail by long pec stage (50h). The organs deposited in its wake are now known as neuromasts. Remnants of the posterior primordium differentiate into neuromasts at the tail tip.

Parents (forms from): cranial placodal ectoderm (lateral line placodes), anterior and posterior to the otic vesicle. These give rise to migratory primordia, which travel beneath the periderm over the body surface, depositing clusters of cells as they go, which differentiate into the neuromasts.

Children:

• Presumptive (thought to give rise to): Unknown
• Anlage (known to give rise to): Lateral line neuromasts, hair cells,, supporting cells, lateral line ganglia

Group (member of):

• Anatomical (group member): Peripheral nervous system
• Functional (group member): Sensory nervous system

Markers:

• mRNA:
  eya1 (Sahly et al., 1999)
  kal1a, kal1b (Ardouin et al., 2000)
  kit (Parichy et al., 1999)
  
  
• Antibodies:
  
  Acetylated tubulin (nerve axons; kinocilia of hair cells)
  anti-Hu (neuronal cell bodies in all cranial ganglia)


• Other:
  
  Vital dyes:
  
  DASPEI (2-(4-dimethylaminostyryl)-N-ethyl pyridinium iodide) (Molecular Probes)
  FM1-43 (N-(3-triethylammoniumpropyl)-4-(4-[dibutylaminostyryl) pyridinium dibromide) (Molecular Probes) (Seiler and Nicolson, 1999)
  4-Di-2-Asp (4-(4-diethylaminostyryl)-N-methylpyridinium iodide (Sigma D-3418) (Collazo et al., 1994)
  fluorescein- or Alexa phalloidin (stains actin in hair bundles)

Publications:

• Primary:
  Metcalfe, W. K. (1985). Sensory neuron growth cones comigrate with posterior lateral line primordial cells in zebrafish. Journal of Comparative Neurology 238, 218-224.
• Secondary:
  Alexandre, D., and Ghysen, A. (1999). Somatotopy of the lateral line projection in larval zebrafish. Proceedings of the National Academy of Sciences USA 96, 7558-7562.

  Ardouin, O., Legouis, R., Fasano, L., David-Watine, B., Korn, H., Hardelin, J., and Petit, C. (2000). Characterization of the two zebrafish orthologues of the KAL-1 gene underlying X chromosome-linked Kallmann syndrome. Mechanisms of Development 90, 89-94.

  Collazo, A., Fraser, S. E., and Mabee, P. M. (1994). A dual embryonic origin for vertebrate mechanoreceptors. Science 264, 426-430.

  Kimmel, C. B., Ballard, W. W., Kimmel, S. R., Ullmann, B., and Schilling, T. F. (1995). Stages of embryonic development of the zebrafish. Developmental Dynamics 203, 253-310.

  Kozlowski, D. J., Murakami, T., Ho, R. K., and Weinberg, E. S. (1997). Regional cell movement and tissue patterning in the zebrafish embryo revealed by fate mapping with caged fluorescein. Biochemistry and Cell Biology 75, 551-562.

  Metcalfe, W. K., Kimmel, C. B., and Schabtach, E. (1985). Anatomy of the posterior lateral line system in young larvae of the zebrafish. Journal of Comparative Neurology 233, 377-389.

  Nicolson, T., Rüsch, A., Friedrich, R. W., Granato, M., Ruppersberg, J. P., and Nüsslein-Volhard, C. (1998). Genetic analysis of vertebrate sensory hair cell mechanosensation: the zebrafish circler mutants. Neuron 20, 271-283.

  Parichy, D. M., Rawls, J. F., Pratt, S. J., Whitfield, T. T., and Johnson, S. L. (1999). Zebrafish sparse corresponds to an orthologue of c-kit and is required for the morphogenesis of a subpopulation of melanocytes, but is not essential for hematopoiesis or primordial germ cell development. Development 126, 3425-3436.

  Raible, D. W., and Kruse, G. J. (2000). Organisation of the lateral line system in embryonic zebrafish. Journal of Comparative Neurology 421, 189-198.

  Sahly, I., Andermann, P., and Petit, C. (1999). The zebrafish eya1 gene and its expression pattern during embryogenesis. Development, Genes and Evolution 209, 399-410.

  Seiler, C., and Nicolson, T. (1999). Defective calmodulin-dependent rapid apical endocytosis in zebrafish sensory hair cell mutants. Journal of Neurobiology 41, 424-434.

  Whitfield, T. T., Granato, M., van Eeden, F. J. M., Schach, U., Brand, M., Furutani-Seiki, M., Haffter, P., Hammerschmidt, M., Heisenberg, C.-P., Jiang, Y.-J., Kane, D. A., Kelsh, R. N., Mullins, M. C., Odenthal, J., and Nüsslein-Volhard, C. (1996). Mutations affecting development of the zebrafish inner ear and lateral line. Development 123, 241-254.

Comments: A study by (Collazo et al., 1994) suggests that there may be a small neural crest contribution to the lateral line.