Immune-related zinc finger gene ZFAT is an essential transcriptional regulator for hematopoietic differentiation in blood islands

Abstract

TAL1 plays pivotal roles in vascular and hematopoietic developments through the complex with LMO2 and GATA1. Hemangioblasts, which have a differentiation potential for both endothelial and hematopoietic lineages, arise in the primitive streak and migrate into the yolk sac to form blood islands, where primitive hematopoiesis occurs. ZFAT (a zinc-finger gene in autoimmune thyroid disease susceptibility region / an immune-related transcriptional regulator containing 18 C 2 H 2 -type zinc-finger domains and one AT-hook) was originally identified as an immune-related transcriptional regulator containing 18 C 2 H 2 -type zinc-finger domains and one AT-hook, and is highly conserved among species. ZFAT is thought to be a critical transcription factor involved in immune-regulation and apoptosis; however, developmental roles for ZFAT remain unknown. Here we show that Zfat -deficient ( Zfat −/− ) mice are embryonic-lethal, with impaired differentiation of hematopoietic progenitor cells in blood islands, where ZFAT is exactly expressed. Expression levels of Tal1 , Lmo2 , and Gata1 in Zfat −/− yolk sacs are much reduced compared with those of wild-type mice, and ChIP-PCR analysis revealed that ZFAT binds promoter regions for these genes in vivo. Furthermore, profound reduction in TAL1, LMO2, and GATA1 protein expressions are observed in Zfat −/− blood islands. Taken together, these results suggest that ZFAT is indispensable for mouse embryonic development and functions as a critical transcription factor for primitive hematopoiesis through direct-regulation of Tal1 , Lmo2 , and Gata1. Elucidation of ZFAT functions in hematopoiesis might lead to a better understanding of transcriptional networks in differentiation and cellular programs of hematopoietic lineage and provide useful information for applied medicine in stem cell therapy.

Identification of Six Loci Associated With Pelvic Organ Prolapse Using Genome-Wide Association Analysis

“…The ZFAT gene has been found to play a transcriptional regulator role for immune regulation and apoptosis. 30 ZFAT might be involved in development of mesodermal cells, 31 and hence may affect development of muscle and connective tissue of the pelvic floor. The collagen XVIII ( COL18A1 ) gene is another interesting candidate gene for POP.…”

ZFAT is a critical molecule for cell survival in mouse embryonic fibroblasts

“…Recently, we demonstrated that Zfat-deficiency (Zfat -/-) is lethal for mice by embryonic day (E) 8.5, with a reduction in the number of blood islands and hematopoietic progenitor cells. ZFAT directly regulates the transcription factors including Tal1, Lmo2 and Gata1 in the blood islands [6]. We also reported that ZFAT is essential for endothelial cell assembly and the branch point formation of capillary-like structures in an angiogenesis model, suggesting that ZFAT is a critical transcriptional regulator for endothelial differentiation [7].…”

“…3). ZFAT is highly conserved among ZFAT orthologues from fish to mammalian species [4], and Zfat -/-mice die by embryonic day (E) 8.5 [6], indicating that ZFAT plays pivotal roles in mouse development. ZFAT knockdown by small interfering RNA in MEFs induced apoptosis, supporting the hypothesis that ZFAT is essential for cell survival and plays a critical role in mesoderm-derived cells and mesenchymal cells.…”

“…Output files were then loaded into GeneSpring v11.0 (Agilent Technologies) with per gene normalization to the expression level of the control siRNAtransfected cells. Quantitative RT-PCR was performed using ABI PRISM 7900HT (Applied Biosystems) and Perfect Real Time Support System (TAKARA) [6]. The PCR primer IDs used for each of the 22 genes are listed in Supplementary Tab.…”

“…The total cell lysates were subjected to SDS-PAGE and transferred to Nitrocellulose Transfer Membrane (Whatman). Western blot was done as described previously [6] using anti-ZFAT monoclonal antbody [6] or anti-ERK1 antibody (K-23; Santa Cruz Biotechnology). The signals were detected via enhanced chemiluminescence following the manufacturer's instructions (ECL detection system, Amersham).…”