Subunit beta1 of the nascent polypeptide-associated complex (NAC); involved in protein targeting to mitochondria; peripheral component of cytoplasmic ribosomes; regulates Atg32p phosphorylation to promote respiration-induced mitophagy; enhances DNA binding of the Gal4p; homolog of human BTF3b; EGD1 has a paralog, BTT1, that arose from the whole genome duplication