cargo = heavy burden?

Context:
Like an overprotective parent on the first day of school, a targeting factor sometimes needs a little push to let go of its cargo. Scientists at the European Molecular Biology Laboratory (EMBL) in Grenoble, France, have visualised one such hand-over. They were the first to determine the structure of a ribosome-protein complex involved in carrying nascent proteins out of the cell. Their work, published online today in Nature Structural and Molecular Biology, could increase understanding of illnesses such as cystic fibrosis and some forms of Parkinson’s disease, in which improper protein targeting leads proteins to harmfully accumulate inside cells.