PNS expression patterns (1)


        Expression pattern in the embryonic PNS at stage 15-17 is schematized here. Black cells are cells that accumulate high levels of the marker, whereas grey cells accumulate low levels and white cells do not accumulate the marker. Cells for which the expression has not been studied are represented by a light grey line. Expression pattern at earlier embryonic stages is also mentioned in the text below each diagram.
          Click on a marker name to link to the corresponding FlyBase page.



Abrupt is expressed in the class I neurons (vpda, ddaD and ddaE) as well as in vbd and dbd (Sugimura et al., 2004; Li et al., 2004).

alpha85E-tubulin is detected in cap cells, attachment cells and  ligament cells of  chordotonal organs (Matthews et al., 1990).  It accumulates also in the ligament-attachment cell of the lch5 organ (not represented in the diagram) (Inbal et al., 2004). Rarely, two ligament-attachment cells are observed close to a lch5 organ (Inbal et al., 2004).

Collier = Knot

blimp-1 is expressed in all the atonal-lacZ-expressing SOP cells (Ng et al., 2006), which will give rise to chordotonal organs.  Blimp-1 protein and mRNA share the same temporal and spatial expression (Ng et al., 2006).
described in Orgogozo et al., 2004. Same pattern as B6-2-25 and Pickpocket. This marker stains the class IV md neurons (Grueber et al., 2002).
The Cut accumulation pattern has been primarily described in Blochinger et al., 1990. Its specific expression in multidendritic neurons is detailed in Grueber et al., 2003. During earlier stages, Cut accumulates in primary precursor cells of all external sensory organs and all the multidendritic neurons that have been shown to originate from an md-es or md-solo lineage, as well as in their progeny cells. Note that vbd does not accumulate Cut at stage 16-17 but its precursor cells do accumulate Cut (md-es lineage).


This cytochrome P450 accumulates in the apical region of socket cells (Willingham and Keil, 2004).




Since the Gal4 enhancer-trap c929, which is inserted in the dimmed gene, is expressed in the lbd neuron (Hewes et al., 2003), Dimmed probably accumulates in the lbd neuron. Anti-Dimmed antibodies have been described in Allan et al. 2005 paper.

At stage 15, Rfx/dRFX is found predominantly in nuclei of all chordotonal (ch) and external sensory (es) organ neurons, and, at a lower level, in the accessory sister cells resulting from the last asymmetric division of the precursors (Vandaele et al., 2001). At stage 16 of embryogenesis, Rfx progressively disappears in the accessory sister cells and is only maintained in es and ch neuron nuclei at the end of embryogenesis. 
Elav accumulates in all sensory neurons (Robinow and White, 1991). Elav is also detected at a lower level in the vp1-vp4a lineages (pIIa, pIIb, pIIIb cells) (V. Orgogozo and F. Schweisguth, personal observations).  Furthermore, at stage 16, a cortical staining is also observed specifically in the sheath cell of all external sensory organs and in the scolopale cell of all chordotonal organs with rat anti-Elav antibodies from DSHB. This staining might not be related to Elav (V. Orgogozo and F. Schweisguth, personal observations).

Erect wing

Erect wing accumulates in all the PNS neurons (DeSimone and White, 1993).

Glial cells missing = Glide

Engrailed accumulates faintly in all the lch5 cells (this expression pattern is probably related to the precursor cells' originating from the posterior part of the segment), as well as in dmd1 and lbd neurons (Brewster et al., 2001).
Glial cells missing accumulates in ligament cells of chordotonal organs and in glial cells originating from the CNS and PNS (Jones et al., 1995). One of the glial cells is associated with the dbd neuron (Fredieu and Mahowald, 1989). Same pattern as Repo and Wrapper.


Gooseberry neuro accumulates in a single cell in the ventral epidermis (Gutjahr et al., 1993) that is located near the vbd neuron (V. Orgogozo and A. Moore, personal observations). This cell may thus be a glial cell associated to vbd.
Hamlet accumulation disappears at stage 15.  It is expressed in the PNS from stage 11 through stage 15. Within the md-es lineage, Hamlet starts to accumulate in pIIIb cell and its progeny cells (neuron and sheath cell). Hamlet quickly disappears in the sheath cell and continues to be expressed by the differentiating neuron up to stage 15 (Moore et al., 2002).
Krüppel is not detected in the PNS at stage 15-17. It is expressed in the PNS from stage 11 through stage 15. In the ventral region, Krüppel is detected only in the vp1, vp2 and vp4a lineages and not in the vmd1a, vp3 and vp4a lineages (vp5 not analyzed). In these three lineages, Krüppel accumulates in pIIa, pIIb, pIIIb and the multidendritic neuron (V. Orgogozo and F. Schweisguth, personal observations).

Kruppel homolog 1


Nubbin = Pdm1

Beck et al. 2004 paper indicates that Kruppel homolog 1 accumulates in all the PNS neurons. However,  there is one exception: it does not accumulates in the  lbd neuron (V. Orgogozo and A.W. Moore, personal observations).

Ladybird accumulates specifically in the vbd neuron (De Graeve et al., 2004).

Nubbin accumulates in dbd and its sibling glial cell, dmd1 and the ligament cells of chordotonal organs (Brewster et al., 2001).  At stage 12-14, Nubbin accumulates at a low level in the primary precursor cells of the dbd and dmd1 neurons, and at a higher level in their daughter cells just after division (Umesono et al., 2002).


Pax2 = Shaven = Sparkling

Onecut accumulates in PNS cells at stage 15 (Nguyen et al., 2000). According to their position, the Onecut-expressing cells are probably PNS neurons.

Pax2 accumulates in the shaft and sheath cells of all external sensory organs (Kavaler et al., 1999; Moore et al., 2004). The exact Pax2 accumulation pattern in chordotonal organs and multidendritic neurons has not been investigated. During md-es lineages, Pax2 accumulates at a low level in primary precursor cells and their progeny cells pIIa, pIIb and pIIIb, in addition to the socket and sheath cells (Moore et al., 2004).
Paired accumulates only in the neurons of vch1, vch2 and lch1. It is not detected in the lch5 neurons (V. Orgogozo and F. Schweisguth, personal observations).

peptidylglycine-alpha-hydroxylating monooxygenase (Phm)

Phm accumulates in the lbd neuron (Hewes et al., 2003).

Pickpocket = mdNaC1
Pox neuro


described in Adams et al., 1998. Same pattern as B6-2-25 and Collier. This marker stains the class IV md neurons (Grueber et al., 2002).
Pox-neuron accumulates in a cell closely associated with each of the four hair es organs dh1dh2, lh1 and lh2 (Awasaki and Kimura, 2001). This cell is presumably the hair-secreting shaft cell. In poxn mutants, hairs are replaced by papilla-like structures (Awasaki and Kimura, 2001).

According to in situ stainings, pdm2 is expressed in the same embryonic PNS cells as nubbin/pdm1 (Llyod et al., 1991; Dick et al., 1991).  Anti-Pdm2 antibodies are described in Yeo et al., 1995.



Pyrexia accumulates in multidendritic neurons as well as in non-multidendritic neurons in larval epidermis (Lee et al., 2005) but its specific expression pattern has not been characterized.

Prospero accumulates in the sheath cell of all external sensory organs as well as all scolopale cells of chordotonal organs (Doe et al., 1991; Vaessin et al., 1991).

Repo = Reverse Polarity

Repo accumulates in ligament cells of chordotonal organs and in glial cells originating from the CNS and PNS (Campbell et al., 1994; Halter et al., 1995; Xiong et al., 1994; Umesono et al., 2002). One of the glial cells is associated with the dbd neuron (Fredieu and Mahowald, 1989). Same pattern as Glial cells missing and Wrapper.
Runt only accumulates in one sensory cell in the ventral region, the socket cell or the shaft cell of the vp3 organ (undetermined, V. Orgogozo and F. Schweisguth, personal observations). Runt accumulation pattern in the lateral and dorsal regions has not been investigated.
At stage 15-17, Senseless only accumulates in the vtd2 neuron (V. Orgogozo, personal observations).  It also accumulates in a subepidermal cell located near vp5, which is part of a three-cell epidermal gland (V. Orgogozo and F. Schweisguth, unpublished results).  At stage 10-14, Senseless accumulates in the primary precursor cells of external sensory organs, chordotonal organs and multidendritic neuron (Nolo et al., 2000). The staining then decreases gradually in the progeny cells and is lost first in the pIIa progeny cells .

Sloppy paired

At stage 14, Sequoia is detected in nuclei of neuron and sheath cells but not the socket and shaft cells (Brenman et al., 2001). By late stage 16, Sequoia is most abundant in neurons but not detectable in sheath cells. Sequoia accumulates in all the Elav-positive neurons of the drosal region at stage 16.
Sloppy-paired is not detected in the ventral PNS at stage 15-17.  It is expressed in the PNS from stage 11 through stage 15. In the ventral region, Sloppy-paired accumulates only in the vp1, vp2, vp4 and vp4a lineages but not in the vp3 lineage (vp5 not analyzed).  In these lineages, it accumulates at a high level in the pI cell, decreases in the pIIa-pIIb cell pair and then disappears (V. Orgogozo and F. Schweisguth, personal observations).
Spineless accumulates in all the PNS neurons (Duncan et al., 1998; Kim et al., 2006).

Suppressor of Hairless
target of Poxn

Suppressor of Hairless accumulates at a high level in the socket cell of all external sensory organs (Gho et al., 1996; Barolo et al., 2000). A GFP reporter gene under the control of a Suppressor of Hairless regulatory region is also very specifically expressed in all external sensory organ socket cells (Barolo et al., 2000).
Target of Poxn accumulates only in the anterior es neuron of the bi-innervated vp5 organ (Gautier et al., 1997). Expression appears  once all the sensory cells are formed.


Wrapper accumulates in ligament cells of chordotonal organs and in glial cells originating from the CNS and PNS (Noordermeer et al., 1998). One of the glial cells is associated with the dbd neuron (Fredieu and Mahowald, 1989). Same pattern as Glial cells missing and Repo.


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