Component of the SSU processome, a pre-ribosomal particle required for the maturation of the 18S rRNA from the 35S pre-rRNA precursor. Component of the ribosomal small subunit (SSU) processome, composed of the 35S pre-rRNA precursor, the U3 snoRNA, and at least 40 protein subunits. Interacts with U3 snoRNA. Belongs to the UTP6 family.