This is a fluorescence image of a neuron labeled for excitatory synapses (green) and cell structure (magenta). SRPX2 was identified in a high throughput screen for synaptogenic molecules. SRPX2 was found to promote excitatory synapse formation under control of the language-associated transcription factor FOXP2. Loss of SRPX2 impairs synapse formation and ultrasonic vocalization in mice, indicating that this may represent a pathway crucial for circuit formation underlying language development. This image relates to a paper that appeared in the 31 Oct., 2013, issue of Science Express, published by AAAS. The paper, by Gek-Ming Sia at the Howard Hughes Medical Institute in Baltimore, MD, and colleagues was titled, "The Human Language-Associated Gene SRPX2 Regulates Synapse Formation and Vocalization in Mice."