GEOOtherMus musculus Expression profiling by high throughput sequencingOtherhttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE324886GEOGSEfalseThe ER Anchoring and Abundance of the EEF1B Complex is Affected by Tissue Specific Alternative EEF1D SpicingThe EEF1B complex plays a central role in translation elongation by reactivating EEF1A for delivery of aminoacyl-tRNAs to the ribosome. Among its components, EEF1D undergoes alternative splicing to produce one long and several short isoforms, each with distinct N-terminal domains and tissue-specific expression patterns. Although the short isoforms are broadly expressed, their functional significance has remained unclear. In this study, we show that short EEF1D isoforms containing exon 5 interact with endoplasmic reticulum (ER)-resident scaffold protein KTN1 and RRBP1, thereby anchoring the EEF1B complex to the ER. Mass spectrometry of FLAG-tagged EEF1D identified these interactions, and deletion of exon 5 disrupted ER anchoring, resulting in diffuse cytoplasmic localization of the EEF1B complex. In exon 5 knockout mice, this altered localization was accompanied by reduced EEF1B subunit abundance in multiple tissues, including liver, although global protein synthesis rates remained unaffected. These findings uncover an ER-anchoring mechanism controlled by alternative splicing that shapes the spatial organization and abundance of the elongation machinery in vivo.2026/05/31GSE324886GSM9588317GSM9588328GSM9588329GSM9588318GSM9588319GSM9588324GSM9588325GSM9588326GSM9588327GSM9588316GSM9588320GSM9588331GSM9588321GSM9588322GSM9588323GSM958833021273324886Mus musculus