J Comp Neurol. in the Fd 105 fovea. Across peripheral retina, opsin appears 1st in rods, adopted about 1 week later on by M&L cone opsin. S cone opsin appears last, and all opsins reach the retinal edge by 1 week after birth. Cone transducin and pole arrestin are indicated concurrently with opsin, but cone arrestin appears slightly later on. Marmoset photoreceptor development differs from that in and humans. It starts relatively late, at 56% gestation, compared with at 32% gestation. The marmoset opsin manifestation sequence is also different from that of either or human being. monkeys for experimental investigation of primate retinal development. Their smaller size, quick maturation, and more frequent breeding with multiple births provide significant cost and time savings when studying primate retinal development. In Eteplirsen (AVI-4658) a earlier paper (Hendrickson et al., 2006), we showed the marmoset retina and its vasculature have a spatial developmental pattern that is identical to earlier morphological descriptions of fetal and infant macaque and human being retinal development (Hendrickson and Kupfer, 1976; Provis et al., 1985, 1998; Yuodelis and Hendrickson, 1986; Packer et al., 1990; LaVail et al., 1991; Hendrickson and Drucker, 1992; Hendrickson, 1992; Dorn et al., 1995; Bumsted et al., 1997; Georges et al., 1999; Xiao and Hendrickson, 2000; Provis, 2001; Springer and Hendrickson, 2004; Hendrickson and Provis, 2006). The one designated difference between macaque and marmoset is in the temporal development of the fovea, the specialized region responsible for high visual acuity. At birth, the marmoset fovea is definitely relatively immature compared with a macaque neonate, but it then undergoes a rapid postnatal development with foveal morphology, suggesting the fovea may be mature within 8C12 weeks (wk) postnatally (Hendrickson et al., 2006). This is much faster than macaque monkey fovea development, which requires 12C15 months to reach adult cone denseness and pit morphology (Hendrickson and Kupfer, 1976; Packer et al., 1990), or human being fovea development, which calls for 4C6 years (Hendrickson and Yuodelis, 1984; Yuodelis and Hendrickson, 1986). If confirmed by ongoing quantitative steps, this quick postnatal development in marmosets significantly shortens the time required to reach a mature endpoint in experimental studies of eye growth, amblyopia, and emmetropization. Many studies in humans and macaque monkeys (for evaluate observe Hendrickson and Provis, 2006) and our recent study in marmoset (Hendrickson et al., 2006) have emphasized that developmental differentiation/maturation begins 1st in the incipient foveal region and ends weeks to weeks later on in the much peripheral retina. For instance, cones within the macaque fovea express synaptic markers at fetal day time (Fd) 55C60 (Okada et al., 1994), just days after the fovea is definitely first recognized morphologically (Hendrickson, 1992), but these same markers do not appear in much peripheral cones until Fd 125C135. Macaque cone opsins, synaptic proteins, and FZD7 phototransduction proteins (Sears et al., 2000) and human being synaptic proteins, opsins, and photoreceptor transcription factors (Georges et al., 1999; Milam et al., 2000; Xiao and Hendrickson, 2000; Swain et al., 2001; Bumsted OBrien et al., 2004) all display a similar early central to later on peripheral manifestation pattern. These findings show that central cones are forming practical synapses with bipolar and/or horizontal cells at an early stage of retinal development, but this process takes many weeks to be completed across the peripheral retina. Given Eteplirsen (AVI-4658) the relatively rapid late fetal and neonatal development of marmoset fovea (Hendrickson et al., 2006), we predict that spatial-temporal manifestation patterns for major photoreceptor proteins might also occur relatively late in gestation. This was tested by using well-characterized antisera for immunocytochemical labeling of primate retina. Our results show that all proteins are indicated inside a temporal/spatial sequence similar to that of macaque, but with their manifestation initiated relatively late in gestation. Surprisingly, the marmoset temporal Eteplirsen (AVI-4658) opsin sequence is different from that of either macaque or Eteplirsen (AVI-4658) humans. MATERIALS AND METHODS Tissue processing All cells was acquired under approved University or college Eteplirsen (AVI-4658) of Washington Institutional Animal Care Committee protocols from cells programs at San Antonio Primate Center, Wisconsin Regional Primate Center, and New England College of Optometry. Marmoset monkeys included in this study were Fd 75 (n = 1), Fd 88 (n = 2), Fd 100C110 (n = 3), Fd 125 (n = 2 twins), Fd 133C135 (n = 3 triplets), postnatal (P) 0.5C2 days (n = 8), P 7C10 days (n = 4), P one month (n = 2), P 2C4 weeks (n = 4), P 6C8 weeks.