Signal sequence-independent targeting of MID2 mRNA to the endoplasmic reticulum by the yeast RNA-binding protein Khd1p.

Localization of mRNAs depends on specific RNA-binding proteins (RBPs) and critically contributes not only to cell polarization but also to basal cell function. The yeast RBP Khd1p binds to several hundred mRNAs, the majority of which encodes secreted or membrane proteins. We demonstrate that a subfraction of Khd1p associates with artificial liposomes and endoplasmic reticulum (ER), and that Khd1p endomembrane association is partially dependent on its binding to RNA.

The structure of the Myo4p globular tail and its function in ASH1 mRNA localization.

Type V myosin (MyoV)-dependent transport of cargo is an essential process in eukaryotes. Studies on yeast and vertebrate MyoV showed that their globular tails mediate binding to the cargo complexes. In Saccharomyces cerevisiae, the MyoV motor Myo4p interacts with She3p to localize asymmetric synthesis of HO 1 (ASH1) mRNA into the bud of dividing cells.

Asymmetric localization of the adaptor protein Miranda in neuroblasts is achieved by diffusion and sequential interaction of Myosin II and VI.

The adaptor protein Miranda plays a pivotal role in the asymmetric cell division of neuroblasts by asymmetrically segregating key differentiation factors. Miranda localization requires Myosin VI and Myosin II. The apical-then-basal localization pattern of Miranda detected in fixed tissue, and the localization defects in embryos lacking Myosin VI, suggest that Miranda is transported to the basal pole as a Myosin VI cargo.

Placental vascularisation requires the AP-1 component fra1.

Fra1 is an immediate-early gene encoding a member of the AP-1 transcription factor family, which has diverse roles in development and oncogenesis. To determine the function of Fra1 in mouse development, the gene was inactivated by gene targeting. Foetuses lacking Fra1 were severely growth retarded and died between E10.

Expression of the RNA recognition motif-containing protein SEB-4 during Xenopus embryonic development.

RNA binding proteins play key roles in the post-transcriptional regulation of gene expression. Here we present the molecular cloning and spatio-temporal expression of Xseb-4, which codes for a putative RNA binding protein containing a single RNA recognition motif (RRM). XSEB-4 shares 60-65% identity with the mammalian SEB-4 proteins.