“…The high level of Thy‐1 expression in adulthood is similar to that observed for BIG‐1, BIG‐2, Kilon, and CEPU‐1, but these other molecules exhibit a highly restricted regional distribution (Yoshihara et al, 1994,Yoshihara et al, 1995; Hosoya et al, 1995; Struyk et al, 1995; Spaltmann and Brummendorf, 1996; Funatsu et al, 1999). Similarly, LAMP and OBCAM, markers for neurons comprising the limbic and olfactory systems, respectively (Levitt, 1984; Horton and Levitt, 1988; Zhukareva and Levitt, 1995; Hachisuka et al, 1996; Pimenta et al, 1996), play functional roles in the establishment of connectivity within these specific neural systems (Keller et al, 1989; Pimenta et al, 1995; Mann et al, 1998). The widespread localization of Thy‐1 across thalamic relay nuclei related to somatosensory, visual, motor, and limbic systems in adults suggests that Thy‐1 is probably not, therefore, involved in providing system‐specific guidance or maturation cues.…”