instruction:
In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.
question:
This results in a decreased secretion of immunoglobulin A , and , consequently , a decreased resistance against infections .
answer:
immunoglobulin A

question:
This difference between SP - 1 and SP - 2 peptides was not due to their differential uptake by cell , since approximately 100 times more SP - 2 peptide could be found in cytoplasmic extracts than SP - 1 peptide in experiments using radiolabeled peptides .
answer:
SP - 1

question:
To further identify the residues responsible for the activity , we isolated the mutant viruses that were not neutralized with the soluble form of MHV receptor proteins , since such mutants were expected to have mutations in amino acids responsible for receptor - binding activity .
answer:
MHV receptor proteins