Hoxc12 expression pattern in developing and cycling murine hair follicles

Abstract

We examine the Hoxc12 RNA expression pattern during both hair follicle morphogenesis and cycling in direct comparison to its only upstream neighbor, Hoxc13. Expression of both genes is restricted to the epidermal part of the follicle excluding the outer root sheath and interfollicular epidermis in a distinct stage-dependent and cyclical manner. During the progressive growth phase (anagen) of developing and cycling follicles, the distinct proximo-distal expression domain of Hoxc12 overlaps only proximally, at the upper-most region of the bulb, with the more proximally restricted Hoxc13 domain. This arrangement of the expression domains of the two genes along the proximal-toward-distal axis of increasing follicular differentiation correlates with the sequential expression of first Hoxc13 and then Hoxc12. This indicates a reversal of the typical temporal colinearity of Hox gene activation otherwise observed along the anterior-posterior morphogenetic axis of the embryo (review: Cell 78 (1994) 191).

Krtap16, Characterization of a New Hair Keratin-associated Protein (KAP) Gene Complex on Mouse Chromosome 16 and Evidence for Regulation by Hoxc13

“…7D) previously reported in both mouse and human hair follicles at RNA (19,38), as well as both RNA and protein levels (21), respectively. Furthermore, this apparent Hoxc13 expression is shifted toward the keratogenous zone of the cortex in GC13 mutant hair follicles (Fig.…”

“…The first is based on indirect regulation mediated by another transcription factor, whose expression might directly be controlled by Hoxc13. A good candidate for this is Hoxc12, whose expression domain in the cortex and precortex of differentiated hair follicles conspicuously overlaps with both the Hoxc13 domain (38) and the Krtap16 expression domains (Fig. 4).…”

Hox in hair growth and development

“…This assumption is supported by preliminary data indicating that Hox genes exhibit spatially restricted expression in a stage-specific manner during folliculogenesis, as well as in cycling hair. For example, murine Hoxa4 has been shown to be expressed only during follicle morphogenesis , whereas Hoxc13 and Hoxc12 are activated sequentially and cyclically during the hair cycle (Shang et al 2002). Combined, the complexity of the spatio-temporal Hox expression patterns in hair suggests that this group of transcriptional regulators assumes a broad spectrum of functions in both developing and cycling follicles.…”

Hair follicle renewal: organization of stem cells in the matrix and the role of stereotyped lineages and behaviors

“…These include Shh (Oro and Higgins, 2003), Wnt genes , Bmp genes (Botchkarev, 2003;Kulessa et al, 2000), Fgf genes (Petiot et al, 2003), Notch family members and their ligands (Pan et al, 2004), together with many transcription factors [e.g. Lef1/Tcf , Krox20 (Gambardella et al, 2000), Gata3 (Kaufman et al, 2003), and Msx1 and Msx2 (Ma et al, 2003)] as well as some belonging to the Hox complex (Hoxc12 and Hoxc13) (Shang et al, 2002).…”