Narrow-line Seyfert 1 galaxies ( NLS1 ) are an intriguing subclass of active galactic nuclei .
Their observed properties indicate low central black hole mass and high accretion rate .
The extremely radio-loud NLS1 sources often show relativistic beaming and are usually regarded as younger counterparts of blazars .
Recently , the object SDSS J110006.07 + 442144.3 was reported as a candidate NLS1 source .
The characteristics of its dramatic optical flare indicated its jet-related origin .
The spectral energy distribution of the object was similar to that of the \gamma -ray detected radio-loud NLS1 , PMN J0948 + 0022 .
Our high-resolution European Very Long Baseline Interferometry Network observations at 1.7 and 5 GHz revealed a compact core feature with a brightness temperature of \gtrsim 10 ^ { 10 } K. Using the lowest brightness temperature value and assuming a moderate Lorentz factor of \sim 9 the jet viewing angle is \lesssim 26 ^ { \circ } .
Archival Very Large Array data show a large-scale radio structure with a projected linear size of \sim 150 kpc reminiscent of double-sided morphology .