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:
 Inhibition of Raf - 1 signaling by a monoclonal antibody , which interferes with Raf - 1 activation and with Mek substrate binding .
answer:
Raf - 1


question:
 The other end of this cluster contained the human type I cytokeratin K20 and K12 gene loci .
answer:
K12 gene


question:
 The hyperpigmentation is linked to the presence of numerous single melanosomes and polymelanosomes in keratinocytes at all levels of the epidermis , and in dermal Factor XIIIa - positive dendrocytes .
answer:

Factor XIIIa