Gene Expr Patterns
September 1, 2016;
Expression of the insulinoma-associated 1 (insm1) gene in Xenopus laevis tadpole retina and brain.
The insulinoma-associated 1 (insm1
) gene is involved in the differentiation of several neuronal and endoderm
derived cell types. insm1
is expressed in the retina
of several vertebrates including Xenopus laevis. We report the detailed expression pattern of insm1
in the X. laevis tadpole retina
. X. laevis insm1
is expressed in most of the ciliary marginal zone
of the mature retina
and the optic tectum
, dorsal pallium
and preoptic areas of the developing tadpole brain
. Overall, insm1
is expressed in regions of the tadpole brain
harboring populations of progenitor cells.
Gene Expr Patterns
[+] show captions
Fig. 1. insm1 is expressed in retinal progenitor cells (RPCs). A. Schematic representation of the mature Xenopus tadpole retina. B – J. In situ hybridization performed using sectioned Xenopus laevis embryos. insm1 is expressed in retinal progenitor cells (RPCs) and undifferentiated neuroepithelium at stage 38. At stages 41 (C, H) and stage 45 (D), insm1 expression was detected in RPCs located in zones 2 and 3 of the ciliary marginal zone (CMZ) but not in the retinal stem cells of zone 1. Compare the expression of insm1 at stage 41 (C, H) to expression of notch1, a zone 2 marker, at stage 41 (F, I). Both are absent in the most distal zone 1 of the CMZ. Also compare the proximal expression of insm1 (C, H) to zone 3 and 4 marker, neuroD at stage 41 (G, J). The CMZ is indicated by black brackets. Scale bars (1 μM) for (B – G) and (H – J) are indicated in (A) and (F), respectively. Abbreviations: GL – ganglion cell layer, INL – inner nuclear layer, PL – photoreceptor layer.
Fig. 2. insm1 expression in the developing brain. A – C. Diagrammatic representation of selected brain regions as viewed in dorsally (A), ventrally (B) or laterally (C). D – L. Whole mount in situ hybridizations of stage 45 dissected brains using probes for insm1 (D – F), foxn4 (G – I), or lhx5 (J – L). insm1 is expressed in the dorsal pallium, optic tectum and rhombomeres as viewed dorsally (D). insm1 expression was also detected ventrally (E) and laterally (F) in the hypothalamus, preoptic area and isthmus. Scale bars (1 μM) are indicated in (D) for (D – F), (G) for (G – I) and (J) for (J – L). Abbreviations: DP – dorsal pallium, H – hypothalamus, IS – isthmus, OB – olfactory bulb, OT – optic tectum, PO – preoptic area, RF – reticular formation, R – rhombomeres.
insm1 (insulinoma associated 1) gene expression in Xenopus laevis dissected brain, assayed via in situ hybridization, NF stage 45, lateral view, anterior right, dorsal up.
Key: H = hypothalamus, OT = optic tectum, PO =preoptic area.
insm1 (insulinoma associated 1) gene expression in sections of Xenopus laevis eye, assayed via in situ hybridization, NF stage 45.