High impact information on pou5f1

• In contrast to the Pou2 product, the t-Pou2 product lacks DNA-binding activity because of its incomplete POU domain structure [1].
• In contrast, overexpression of the t-Pou2 product greatly affected the embryonic development: There was strong developmental retardation or arrest due to the incomplete gastrulation [1].
• Zebrafish pou2 is maternally expressed, and the transcripts are present from the one-cell stage to the gastrula stage [1].
• Consistent with this possibility, Bmp gene misexpression can rescue MZspg embryos, indicating that TGFbeta-mediated signal transduction itself is intact in absence of Pou2 [2].
• Widespread overexpression of Pou2 can rescue the segmental krx20 and val domains in spg mutants, but does not induce ectopic expression of these genes [3].

Biological context of pou5f1

• pou5f1, also known as Oct4, is required to establish the pluripotent cell population necessary for embryogenesis in mouse [4].
• The POU domain protein spg (pou2/Oct4) is essential for endoderm formation in cooperation with the HMG domain protein casanova [5].
• Initially, Pou2 functions during early proliferation and morphogenesis of the blastomeres, similar to Oct3/4 in mammals during formation of the inner cell mass [6].
• Injections of pou2-morpholinos phenocopy the spg phenotype at low concentration, further proving that spg encodes pou2 [6].
• During zebrafish brain formation, Pou2 then functions a second time to activate gene expression in the midbrain and hindbrain primordium, which is reflected at later stages in the specific lack in spg embryos of the MHB and associated defects in the mid- and hindbrain [6].

Anatomical context of pou5f1

• In zebrafish, the zygotic pou5f1/pou2 mutant spiel ohne grenzen (spg) shows neural plate patterning defects and reduced endoderm at the tailbud stage [4].
• spiel ohne grenzen/pou2 is required for zebrafish hindbrain segmentation [3].
• We show that embryos homozygous for spg/pou2 have severe defects in development of the midbrain and hindbrain primordium [7].
• Maternal pou-2 transcripts are initially found in all blastomeres [8].
• Blastula pou-2 expression in confined exclusively to the deep embryonic layer (DEL) forming the embryo proper [8].

Associations of pou5f1 with chemical compounds

• Retinoic acid treatment during epiboly alters the hindbrain domains of pou-2, suggesting that the entire anterior hindbrain acquires r4-like properties [8].

Other interactions of pou5f1

• This suggests that spg/pou2 acts in a permissive manner and is essential for normal expression of krx20 and val [3].

Analytical, diagnostic and therapeutic context of pou5f1

• However, in situ hybridization identified a subpopulation of cells expressing pou-2, suggesting the possible continued existence of undifferentiated stem cells in the cultures [9].

References