May play a role in neurogenesis. May promote matrix mineralization (PubMed:22209847), but has been shown to weakly, but significantly inhibit BMP2 and BMP6 activity in a preosteoblastic cell line (PubMed:19852960). Peripherally associated with AMPAR complex. AMPAR complex consists of an inner core made of 4 pore-forming GluA/GRIA proteins (GRIA1, GRIA2, GRIA3 and GRIA4) and 4 major auxiliary subunits arranged in a twofold symmetry. One of the two pairs of distinct binding sites is occupied either by CNIH2, CNIH3 or CACNG2, CACNG3. The other harbors CACNG2, CACNG3, CACNG4, CACNG8 or GSG1L. This inner core of AMPAR complex is complemented by outer core constituents binding directly to the GluA/GRIA proteins at sites distinct from the interaction sites of the inner core constituents. Outer core constituents include at least PRRT1, PRRT2, CKAMP44/SHISA9, FRRS1L and NRN1. The proteins of the inner and outer core serve as a platform for other, more peripherally associated AMPAR constituents, including VWC2L. Alone or in combination, these auxiliary subunits control the gating and pharmacology of the AMPAR complex and profoundly impact their biogenesis and protein processing. Predominantly expressed in the brain (at protein level). Also detected in bones, including femur and calvaria, heart, lung and kidney. Isoform 5 is predominant in lung and heart, compared to isoforms 1 and 3. Isoform 4 is expressed in femur and calvaria at higher levels than isoforms 1 and 5. Isoforms 1 and 4 are expressed at higher levels than isoform 5 in kidney and brain. From 12.5 dpc to 18.5 dpc, expressed in the developing neural tissues, including several discrete regions in the forebrain, midbrain and hindbrain, as well as in the spinal cord. May be up-regulated in the course of preosteblast differentiation and matrix mineralization.