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John J Ely

Publications and source records attributed to John J Ely.

6 recordsLinked to original sources
PubMed2025

Human-specific features of the cerebellum and ZP2-regulated synapse development.

Understanding the unique features of the human brain compared to non-human primates has long intrigued humankind. The cerebellum refines motor coordination and cognitive functions, contributing to the evolutionary development of human adaptability and dexterity. To identify shared and divergent features across primates, we conducted single-nucleus transcriptomic and chromatin accessibility profiling of the adult cerebellar cortex in humans, chimpanzees, macaques, and marmosets. We revealed human-specific transcriptomic and regulatory features, particularly those involved in synaptogenesis. Notably, we identified an enrichment of the sperm receptor zona pellucida glycoprotein 2 (ZP2) and its potential interactors, known for their roles in gamete interaction, in human granule cells. Experimental data show that ZP2 expression in human granule cells is induced by pontine mossy fibers, reducing synaptic proteins at pontocerebellar glomerular synapses, and decreasing cerebellar neuron electrophysiological activity. This unexpected co-option of ZP2 in human-specific synapse regulation provides insights into the evolutionary specialization of the human cerebellum.

Brain evolution↗
PubMed2006

Twinning and heteropaternity in chimpanzees (Pan troglodytes).

Unlike monozygotic (MZ) twins, dizygotic (DZ) twins develop from separate ova. The resulting twins can have different sires if the fertilizing sperm comes from different males. Routine paternity testing of a pair of same-sexed chimpanzee twins born to a female housed with two males indicated that the twins were sired by two different males. DNA typing of 22 short-tandem repeat (STR) loci demonstrated that these twins were not MZ twins but heteropaternal DZ twins. Reproductive data from 1926-2002 at five domestic chimpanzee colonies, including 52 twins and two triplets in 1,865 maternities, were used to estimate total twinning rates and the MZ and DZ components. The average chimpanzee MZ twinning rate (0.43%) equaled the average human MZ rate (0.48%). However, the chimpanzee DZ twinning rate (2.36%) was over twice the human average, and higher than all but the fertility-enhanced human populations of Nigeria. Similarly high twinning rates among African chimpanzees indicated that these estimates were not artifacts of captivity. Log-linear analyses of maternal and paternal effects on recurrent twinning indicated that females who twinned previously had recurrence risks five times greater than average, while evidence for a paternal twinning effect was weak. Chimpanzee twinning rates appear to be elevated relative to corresponding estimated human rates, making twinning and possibly heteropaternity more important features of chimpanzee reproductive biology than previously recognized.

Animals↗
PubMed2005

Subspecies composition and founder contribution of the captive U.S. chimpanzee (Pan troglodytes) population.

Chimpanzees are presently classified into three subspecies: Pan troglodytes verus from west Africa, P.t. troglodytes from central Africa, and P.t. schweinfurthii from east Africa. A fourth subspecies (P.t. vellerosus), from Cameroon and northern Nigeria, has been proposed. These taxonomic designations are based on geographical origins and are reflected in sequence variation in the first hypervariable region (HVR-I) of the mtDNA D-loop. Although advances have been made in our understanding of chimpanzee phylogenetics, little has been known regarding the subspecies composition of captive chimpanzees. We sequenced part of the mtDNA HVR-I region in 218 African-born population founders and performed a phylogenetic analysis with previously characterized African sequences of known provenance to infer subspecies affiliations. Most founders were P.t. verus (95.0%), distantly followed by the troglodytes schweinfurthii clade (4.6%), and a single P.t. vellerosus (0.4%). Pedigree-based estimates of genomic representation in the descendant population revealed that troglodytes schweinfurthii founder representation was reduced in captivity, vellerosus representation increased due to prolific breeding by a single male, and reproductive variance resulted in uneven representation among male P.t.verus founders. No increase in mortality was evident from between-subspecies interbreeding, indicating a lack of outbreeding depression. Knowledge of subspecies and their genomic representation can form the basis for phylogenetically informed genetic management of extant chimpanzees to preserve rare genetic variation for research, conservation, or possible future breeding.

Africa↗
PubMed2005

The epidemiology of simian immunodeficiency virus infection in a large number of wild- and captive-born chimpanzees: evidence for a recent introduction following chimpanzee divergence.

Simian immunodeficiency virus (SIVcpz) from the chimpanzee subspecies Pan troglodytes troglodytes has been linked phylogenetically to the origin of HIV-1. Related but distinct SIVcpz strains have also been found in P. t. schweinfurthii , suggesting that SIVcpz may have coevolved among the four chimpanzee subspecies. However, SIVcpz strains from P. t. verus and P. t. vellerosus have not yet been identified. To better understand the epidemiology and natural history of SIVcpz among chimpanzees, we tested serum samples from 1415 chimpanzees housed at eight U.S. research centers and six zoos. Records indicated that 264 (18.6%) of the chimpanzees were African-born. Subspecies identities for 161 chimpanzees, based on analysis of mitochondrial DNA sequences, were found to be P. t. troglodytes (n = 14), P. t. schweinfurthii (n = 3), P. t. verus (n = 143), and P. t. vellerosus (n = 1). All samples were screened for HIV/SIV antibodies by using an HIV-1/2 peptide- based enzyme immunoassay (EIA). Reactive samples were tested further by Western blot (WB). Eight sera (0.57%) were EIA reactive, but none was HIV-1/2 WB positive. Two samples were HIV-1 WB indeterminate. Both samples tested negative for SIVcpz and HIV-1 sequences by reverse transcriptase PCR, suggesting an absence of infection. We also tested sera available from 8 male sexual partners, 6 offspring, and 12 cage mates of a known SIVcpz-infected chimpanzee. All samples were negative, suggesting that SIVcpz may not be easily transmitted to close contacts. Our data show that this large population of chimpanzees is not infected with SIVcpz. The absence of SIVcpz infection in P. t. verus suggests that SIVcpz may not be endemic to this subspecies and implies that SIVcpz may have been introduced more recently into the chimpanzee subspecies following divergence.

Animals↗
PubMed2004

Frequent simian foamy virus infection in persons occupationally exposed to nonhuman primates.

The recognition that AIDS originated as a zoonosis heightens public health concerns associated with human infection by simian retroviruses endemic in nonhuman primates (NHPs). These retroviruses include simian immunodeficiency virus (SIV), simian T-cell lymphotropic virus (STLV), simian type D retrovirus (SRV), and simian foamy virus (SFV). Although occasional infection with SIV, SRV, or SFV in persons occupationally exposed to NHPs has been reported, the characteristics and significance of these zoonotic infections are not fully defined. Surveillance for simian retroviruses at three research centers and two zoos identified no SIV, SRV, or STLV infection in 187 participants. However, 10 of 187 persons (5.3%) tested positive for SFV antibodies by Western blot (WB) analysis. Eight of the 10 were males, and 3 of the 10 worked at zoos. SFV integrase gene (int) and gag sequences were PCR amplified from the peripheral blood lymphocytes available from 9 of the 10 persons. Phylogenetic analysis showed SFV infection originating from chimpanzees (n = 8) and baboons (n = 1). SFV seropositivity for periods of 8 to 26 years (median, 22 years) was documented for six workers for whom archived serum samples were available, demonstrating long-standing SFV infection. All 10 persons reported general good health, and secondary transmission of SFV was not observed in three wives available for WB and PCR testing. Additional phylogenetic analysis of int and gag sequences provided the first direct evidence identifying the source chimpanzees of the SFV infection in two workers. This study documents more frequent infection with SFV than with other simian retroviruses in persons working with NHPs and provides important information on the natural history and species origin of these infections. Our data highlight the importance of studies to better define the public health implications of zoonotic SFV infections.

Animals↗