XLMR candidate mouse gene, Zcchc12 (Sizn1) is a novel marker of Cajal–Retzius cells

Abstract

Sizn1 (Zcchc12) is a transcriptional co-activator that positively modulates BMP (Bone Morphogenic Protein) signaling through its interaction with Smad family members and CBP. We have demonstrated a role for Sizn1 in basal forebrain cholinergic neuron specific gene expression. Furthermore, mutations in SIZN1 have been associated with X-linked mental retardation. Given the defined role of SIZN1 in mental retardation, knowing its complete forebrain expression pattern is essential to further elucidating its role in cognition. To better define the dynamic expression pattern of Sizn1 during forebrain development, we investigated its expression in mouse brain development from embryonic day 8.0 (E8.0) to adult. We found that Sizn1 is primarily restricted to the ventral forebrain including the medial ganglionic eminence, the septum, amygdala, and striatum. In addition, Sizn1 expression is detected in the cortical hem and Pallial-subpallial boundary (PSB; anti-hem); both sources of Cajal-Retzius cells. Sizn1 expression in the dorsal forebrain is restricted to a subset of cells in the marginal zone that also express Reln, indicative of Cajal-Retzius cells. These data provide novel information on brain regions and cell types that express Sizn1, facilitating further investigations into the function of Sizn1 in both development and the pathogenesis of mental retardation.

PNMA family: Protein interaction network and cell signalling pathways implicated in cancer and apoptosis

“…could play an important role in the developmental regulation or maintenance of neuronal cells [68]. In addition, mutations of PNMA7A were found to be associated with human mental retardation [40,69]. Currently, it's not clear whether PNMA7A plays a role in neuronal survival or apoptosis; however, recent studies showed that PNMA7A functions as an oncogene and the expression is elevated in thyroid cancer cells [70,71], suggesting than PNMA7A could function to promote neuronal and cancer cell growths.…”

The role of genes domesticated from LTR retrotransposons and retroviruses in mammals

“… Cho et al (2008a) , 2011 reported PNMA10 to be a candidate gene for X-linked mental retardation ( XLMR ) in humans. In mice, Pnma10/Zcchc12 is expressed in the embryonic ventral forebrain in a cholinergic–neuron-specific manner ( Cho et al, 2011 ), and is known to act as a transcriptional co-activator for bone morphogenic protein (BMP) signaling by binding to the SMAD family of proteins ( Cho et al, 2008b ). Therefore, it is likely that PNMA10 is related to the evolution of brain function in mammals.…”

Characterization of hippocampal Cajal-Retzius cells during development in a mouse model of Alzheimer′s disease (Tg2576)

“…Cajal-Retzius cells have recently been suggested to be involved in cognition[ 6 ]. Cajal-Retzius cells may play a role in cognition, such as learning and memory, because alterations in the number of Cajal-Retzius cells have been suggested as a cause of neuronal dysfunction in Alzheimer's disease[ 51 ]. Cajal-Retzius cells and reelin have been implicated in neurological and psychiatric diseases, including Alzheimer's disease[ 25 52 ], temporal lobe epilepsy[ 18 53 ] and autism[ 54 55 ].…”