Centromere repositioning. (1/3)

Primate pericentromeric regions recently have been shown to exhibit extraordinary evolutionary plasticity. In this paper we report an additional peculiar feature of these regions that we discovered while analyzing, by FISH, the evolutionary conservation of primate phylogenetic chromosome IX. If the position of the centromere is not taken into account, a relatively small number of rearrangements must be invoked to account for interspecific differences. Conversely, if the centromere is included, a paradox emerges: The position of the centromere seems to have undergone, in some species, an evolutionary history independent from the surrounding markers. A significant number of additional rearrangements must be proposed to reconcile the order of the markers with centromere position. Alternatively, the evolutionary emergence of neocentromeres can be postulated.  (+info)

First outbreak of callitrichid hepatitis in Germany: genetic characterization of the causative lymphocytic choriomeningitis virus strains. (2/3)

Callitrichid hepatitis (CH) is a highly fatal, rodent-borne zoonosis of New World primates (family Callitrichidae) caused by lymphocytic choriomeningitis virus (LCMV). It is unclear whether virulence in Callitrichidae is associated with specific genetic or phylogenetic markers of the virus as only a partial S RNA sequence of a single CH-associated isolate is known. In a period of 10 months, three pygmy marmosets (Cebuella pygmaea) and one Goeldi's monkey (Callimico goeldii) died from CH in a German zoo. LCMV was most likely transmitted by wild mice. Infection was associated with characteristic histopathological lesions in liver, brain, and lymphoid tissue. Virus sequences from all callitrichids and a captured mouse were > or =99.2% identical. LCMV strains from a pygmy marmoset and the Goeldi's monkey were isolated in cell culture and the 3.4-kb S RNA was completely sequenced. Both strains differed considerably in their genetic and phylogenetic characteristics from known LCMV strains, including the previously described CH-associated strain. These data show that CH is widespread and can be caused by distantly related LCMV strains.  (+info)

Determination of ovarian cycle in Goeldi's monkey (Callimico goeldii) via the measurement of steroids and peptides in plasma and urine. (3/3)

Goeldi's monkey (Callimico goeldii) is an endangered species of New World primate. The present study provides the first description of the non-conception ovarian cycle in this species based on circulating reproductive steroid and peptide hormones. The data obtained were used to validate a non-invasive system for monitoring cyclicity based on urinary reproductive steroid metabolites. Nine sexually mature females were studied. In three females, matched blood and urine samples were collected once every 2-3 days for 90-120 days; in three other females, matched blood and urine samples were collected daily for 14-20 days for one peri-ovulatory period; and in the remaining three females, urine samples only were collected once every 1-3 days for 40-60 days. Plasma progesterone, oestrone-3-conjugates and bioactive LH were measured, in addition to urinary pregnanediol-3 alpha-glucuronide and oestrone-3-conjugates. The mean maximum concentration of plasma LH occurred 1-2 days before a significant rise in plasma progesterone, which was considered to occur 1 day after ovulation. On the basis of plasma progesterone titres, the duration of the ovarian cycle was estimated as 23.9 +/- 0.4 days (n = 9), and constituted a follicular phase of 10.7 +/- 0.3 days and a luteal phase of 13.5 +/- 0.3 days. Urinary pregnanediol-3 alpha-glucuronide demonstrated a high correlation with plasma progesterone (r = 0.8), and demonstrated a significant rise at the same time as plasma progesterone.(ABSTRACT TRUNCATED AT 250 WORDS)  (+info)