Rafael Montiel

• Ph.D.
• Investigador Cinvestav 3-C at Center for Research and Advanced Studies of the National Polytechnic Institute

Archaeological cobs from Paredones and Huaca Prieta (Peru) represent some of the oldest maize known to date, yet they present relevant phenotypic traits corresponding to domesticated maize. This contrasts with the earliest Mexican macro-specimens from Guila Naquitz and San Marcos, which are phenotypically intermediate for these traits, even though...

Archaeological cobs from Paredones and Huaca Prieta (Peru) represent some of the oldest maize known to date, yet they present relevant phenotypic traits corresponding to domesticated maize. This contrasts with the earliest Mexican macro-specimens from Guila Naquitz and San Marcos, which are phenotypically intermediate for these traits, even though...

Significance Despite their importance in supplying nutrients, root traits related to maize domestication are scarce. We used laser ablation tomography to characterize the root architecture and anatomy of 5,300-y-old maize specimens recovered from San Marcos (Tehuacán, Mexico), revealing exquisite preservation of their cellular organization. Outer c...

Archaeological cobs from Paredones and Huaca Prieta (Peru) are phenotypically indistinguishable from modern maize. This contrasts with the earliest Mexican macro-specimens from Guila Naquitz and San Marcos, which are phenotypically intermediate even though they date more recently in time. These observations suggest at least two alternative scenario...

Mitochondria participate in multiple functions in eukaryotic cells. Although disruption of mitochondrial function has been associated with energetic deregulation in cancer, the chronological changes in mitochondria during cancer development remain unclear. With the aim to assess the role of mitochondria throughout cancer development, we analyzed sa...

Este nuevo volumen sobre Teopancazco en la antigua Teotihuacan, que sería el quinto de la serie de resultados de las excavaciones exten-sivas de 1997 a 2005, aborda la población multiétnica del centro de barrio desde sus actividades, sus prácticas funerarias, las marcas de actividad en el esqueleto, la exposición al calor de estos restos humanos; l...

Mycobacterium simiae (Karassova V, Weissfeiler J, Kraszanay E, Acta Microbiol Acad Sci Hung 12:275-82, 1965) is a slow-growing nontuberculous Mycobacterium species found in environmental niches, and recently evidenced as an opportunistic Human pathogen. We report here the genome of a clinical isolate of M. simiae (MsiGto) obtained from a patient in...

A large collection of maize macro-specimens has been gathered from archaeological sites across the American continent, but only a few have been directly dated by accelerator mass spectrometry (AMS). We recently conducted two new excavations in several rock shelters of Tehuacán valley (San Marcos, Coxcatlán, and Purrón) and uncovered 132 non-manipul...

Background The entomopathogenic nematode Steinernema carpocapsae has been used worldwide as a biocontrol agent for insect pests, making it an interesting model for understanding parasite-host interactions. Two models propose that these interactions are co-evolutionary processes in such a way that equilibrium is never reached. In one model, known as...

Autophagy is especially important in disorders where accumulation of the mutant protein is a hallmark, such as the Machado-Joseph disease/spinocerebellar ataxia type 3 (MJD/SCA3). We analyzed the promoter of the BECN1 gene, whose overexpression has been reported to exert neuroprotective effects in MJD, with the aim of finding variants that could be...

Pontoscolex corethrurus (Müller, 1857) plays an important role in tropical soil ecosystems and has been widely used as an animal model for a large variety of ecological studies, in particular due to its common presence and generally high abundance in human-disturbed tropical soils. In this study we describe the complete mitochondrial genome of the...

The ancient city of Teotihuacan was a great urban and ceremonial center, whose population grew exceptionally during the Classic Period (300–700 AC). Settlement patterns, culture and burials have indicated an occupation that consisted of groups of neighboring apartment compounds or barrios. We investigated the genetics of three apartment compounds i...

The story of how pre-Columbian civilizations developed goes hand-in-hand with the process of plant domestication by Mesoamerican inhabitants. Here we present the almost complete sequence of a mitochondrial genome and a partial chloroplast genome from an archaeological maize sample collected at the Valley of Tehuacán, México. Accelerator mass spectr...

Pontoscolex corethrurus (Müller, 1857) plays an important role in soil terrestrial ecosystems and has been widely used as an animal model for a large variety of ecological studies, in particular due to its common presence and generally high abundance in human-disturbed tropical soils. In this study we describe the complete mitochondrial genome of t...

Pontoscolex corethrurus (Müller, 1857) plays an important role in soil terrestrial ecosystems and has been widely used as an animal model for a large variety of ecological studies, in particular due to its common presence and generally high abundance in human-disturbed tropical soils. In this study we describe the complete mitochondrial genome of t...

The ancient city of Teotihuacan was a great urban and ceremonial center, whose population grew exceptionally in the Classic Period (300 – 700 AC). Settlement patterns, culture and burials have indicated an occupation that consisted of groups of neighboring apartment compounds or barrios. We investigated the genetics of three apartment compounds in...

The entomopathogenic nematode Steinernema carpocapsae has been widely used for the biological control of insect pests. It shares a symbiotic relationship with the bacterium Xenorhabdus nematophila, and is emerging as a genetic model to study symbiosis and pathogenesis. We obtained a high-quality draft of the nematode’s genome comprising 84,613,633...

Significance The valley of Tehuacán in Mexico is an important center of early Mesoamerican agriculture. To characterize the genetic constitution of the earliest phase of maize cultivation, we reexamined San Marcos cave in Tehuacán and sequenced DNA from three newly discovered maize samples dating at a similar age of 5,000 y B.P. The genomes of thes...

Objectives To determine ancient population influences on ancient and current Balearic populations and to reconstruct their mitochondrial DNA (mtDNA) gene pool evolution. Methods We analyzed 239 individuals belonging to five archaeological populations from Majorca and Minorca, four dating to the transition between the Bronze Age and the Iron Age, a...

In an attempt to understand the genetic dynamics in Teopancazco, Teotihuacan, weconducted and ancient DNA analysis based on mtDNA.Our results show that the level of genetic diversity isconsistent with the multiethnicity observed through cultural behaviour and isotopic analyses, at this neighborhood center.

Background and Objectives: Autophagy, as a process of lysosomal-dependent intracellular components degradation, is especially important in disorders where accumulation of the mutant protein is a hallmark, such as Machado-Joseph disease (MJD/SCA3; OMIM 109150), a late onset progressive polyglutamine ataxia, considered the worldwide most common autos...

An 84 base pair sequence of the Streptococcus mutans virulence factor, known as dextranase, has been obtained from 10 individuals from the Bronze Age to the Modern Era in Europe and from before and after the colonization in America. Modern samples show four polymorphic sites that have not been found in the ancient samples studied so far. The nucleo...

Overall botanical, archaeological and genetic evidence indicates that maize (Zea mays ssp. mays) was domesticated in Central Mexico approximately 9000 years ago, based on teosinte (Zea mays ssp. parviglumis) from the Balsas; however, a number of questions related to the na- ture of genetic or environmental domestication forces have yet to be addres...

Sex identification in ancient human remains is a common problem especially if the skeletons are sub-adult, incomplete or damaged. In this paper we propose a new method to identify sex, based on real-time PCR amplification of small fragments (61 and 64 bp) of the third exon within the amelogenin gene covering a 3-bp deletion on the AMELX-allele, fol...

##Assembly-Data-START## Assembly Method :: Sequin v. 12.21 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

##Assembly-Data-START## Assembly Method :: Sequin v. 12.21 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

##Assembly-Data-START## Assembly Method :: Sequin v. 12.21 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

##Assembly-Data-START## Assembly Method :: Sequin v. 12.21 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

##Assembly-Data-START## Assembly Method :: Sequin v. 12.21 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

##Assembly-Data-START## Assembly Method :: Sequin v. 12.21 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

##Assembly-Data-START## Assembly Method :: Sequin v. 12.21 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

##Assembly-Data-START## Assembly Method :: Sequin v. 12.21 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

##Assembly-Data-START## Assembly Method :: Sequin v. 12.21 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

##Assembly-Data-START## Assembly Method :: Sequin v. 12.21 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

##Assembly-Data-START## Assembly Method :: Sequin v. 12.21 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

##Assembly-Data-START## Assembly Method :: Sequin v. 12.21 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

Background and Objectives: Autophagy, as a process of intracellular components degradation, is especially important in disorders where accumulation of the mutant protein is a hallmark, such as MJD, a late onset polyglutamine ataxia. We documented the variation in the promoter of the BECN1 gene whose overexpression has been reported to exert neuropr...

The antilisterial activity of edible films that contained 4% w/v sodium caseinate, 30% w/v glycerol, dry-based, and different amounts of antimicrobial substances (AM) produced by Streptococcus sp. ABMX, a lactic acid bacterium isolated from Mexican Pozol, was characterised. The AM were incorporated into the films as concentrated supernatant of cult...

We have amplified DNA from Streptococcus mutans from 6 individuals of different antiquity belonging to the variable region of the dextranase gene and from the European and American continents with the purpose of characterizing the possible geographic and temporary differences that can reflect their evolution and adaptation to its human host. It has...

We have amplified DNA from Streptococcus mutans from 6 individuals of different antiquity belonging to the variable region of the dextranase gene and from the European and American continents with the purpose of characterizing the possible geographic and temporary differences that can reflect their evolution and adaptation to its human host. It has...

Steinernemacarpocapsae is a nematode pathogenic in a wide variety of insect species. The great pathogenicity of this nematode has been ascribed to its ability to overcome the host immune response; however, little is known about the mechanisms involved in this process. The analysis of an expressed sequence tags (EST) library in the nematode during t...

Communities of organisms inhabiting extreme terrestrial environments provide a unique opportunity to study evolutionary forces that drive population structure and genetic diversity under the combined challenges posed by multiple geogenic stressors. High abundance of an invasive pantropical earthworm (and the absence of indigenous lumbricid species)...

Steinernema carpocapsae is an entomopathogenic nematode widely used for the control of insect pests due to its virulence, which is mainly attributed to the ability the parasitic stage has to overcome insect defences. To identify the mechanisms underlying such a characteristic, we studied a novel serpin-like inhibitor (sc-srp-6) that was detected in...

Structural model of Sc-SRP-6. A predicted 3D model was obtained using the ITASSER server with an estimated model accuracy of 0.69±0.12 and a confidence score of −0.15. Recombinant Sc-SRP-6 showing a typical serpin fold comprising three large β-sheets (βA, B and C) and nine α-helices (hA - hI). The S4 β-strand of the βB-sheet has the RCL exposed and...

Activity of Sc-SRP-6 at pH 6, 7, 8 and 9. Activity of Sc-SRP-6 was quantified at pH 6, 7, 8 and 9 using BApNA and Suc-AAPFpNA as a substrates for trypsin and chymotrypsin, respectively. (TIF)

Identification of recombinant Sc-SRP-6 by MALDI-MS/MS. A 54% sequence coverage and a significance score of 462 (P<0.05) was achieved. The confidence threshold for protein identification was set to 95% (p<0.05). Protein identification was performed using MASCOT to search the UniProtKB database (downloaded on 10/06/2012). (DOCX)

Full Sc-SRP-6 cDNA sequence. The sequence is 1,297 bp in length including an 1,191-bp open reading frame (ORF) and a 152-bp 3′ untranslated region with a putative polyadenylation signal (AATAAA). The ORF was predicted to encode a 397-amino- acid polypeptide with a single serpin domain spanning residues 35–396 and associate with a 19-residue pre-pro...

Identification of Sc-SRP-6/hemolymph proteins complex by MALDI-MS/MS. Significance scores were achieved whit confidence threshold for protein identification of 95% (p<0.05). (DOCX)

Background: Autophagy is a process of intracellular components degradation, crucial for the management of insoluble aggregate-prone proteins and essential for neuronal survival. Autophagy is thus thought to be especially important in disorders where accumulation of the mutant protein is a hallmark, such as Machado–Joseph disease (MJD), an auto...

The characterization of biomolecules from ancient samples can shed otherwise unobtainable insights into the past. Despite the fundamental role of transcriptomal change in evolution, the potential of ancient RNA remains unexploited - perhaps due to dogma associated with the fragility of RNA. We hypothesize that seeds offer a plausible refuge for lon...

Calibration curves for dating of 2 Arizona maize kernels. (TIF)

Fraction of total GS FLX reads mapping to the B73 reference genome for cDNA (4) and DNA (3) libraries. The breakdown of reads mapped with BWA before and after removing sequence duplicates and paralogs is shown. Unmapped reads were then mapped using BLAT to retrieve as many endogenous reads as possible. Estimates of endogenous maize nucleic acid con...

Photo of Arizona kernel, batch 935. (TIF)

Ancient RNA (935130) Fragmentation and Misincorporation Plot. (TIF)

Radiocarbon results BP and analytical data, including stable isotope results. All data is acceptable for a material such as this. ‘Used’ is the material analyzed in pretreatment chemistry, whilst ‘yield’ is the amount remaining after the chemical purification procedures applied. (DOCX)

Functionally annotated exon hits for Arizonan kernel 935130. (DOCX)

Ancient DNA (AZ Shotgun) Fragmentation and Misincorporation Plot. (TIF)

Ancient RNA (935230) Fragmentation and Misincorporation Plot. (TIF)

Functionally annotated exon hits for Arizonan kernel 935230. (DOCX)

Detailed methodology, including nucleic acid extraction method, PCR amplification primer sequences and tests, data analyses and radiocarbon dating. (DOCX)

Fraction of total GAIIx (AZ shotgun) and HiSeq (935130 and 935230) reads mapped to the B73 reference genome. BWA (before and after removing sequence duplicates and paralogs) and BLAT mapping values are shown. (DOCX)

Top 50 exon hits with functional annotation from 935130 cDNA maize read. (DOCX)

Repeat content profiles of HiSeq cDNA and GAIIx DNA sequences using RepeatMasker. (DOCX)

Las evidencias morfológicas en restos humanos antiguos podrían indicar que algunos individuos probablemente padecieron una infección bacteriana. En este contexto, los análisis moleculares de ADN antiguo son una herramienta útil para confirmar el diagnóstico macroscópico como lo demuestran el creciente número de publicaciones. Sin embargo, debido a...

Polar bears (PBs) are superbly adapted to the extreme Arctic environment and have become emblematic of the threat to biodiversity from global climate change. Their divergence from the lower-latitude brown bear provides a textbook example of rapid evolution of distinct phenotypes. However, limited mitochondrial and nuclear DNA evidence conflicts in...

Background: Machado-Joseph disease (MJD) is an autosomal dominant spinocerebellar ataxia caused by a CAG tract expansions in the ATXN3 gene. Patterns of mitochondrial damage associated with pathological findings of brain tissues could provide molecular biomarkers of this disorder. Objective: The potential of mitochondrial DNA (mtDNA) damage as a...

The molecular techniques for ancient DNA recovering, offers the possibility to compare the molecular evolution through time as these are tools which make clear possible infectious diseases from the ancient times Objective: To isolate and sequence fossilized Streptococcus mutans DNA fragments, considered the infectious agent involved with dental car...

Alternative splicing (AS) of pre-mRNA is an important regulatory mechanism that enables one gene to produce multiple mature transcripts and, therefore, multiple protein isoforms. Besides the information content of core splicing signals, additional cis-regulatory elements (splicing enhancers and silencers) are needed to precisely define exons. AS is...

Ancient DNA (aDNA) analysis can be a useful tool in bacterial disease diagnosis in human remains. However, while the recovery of Mycobacterium spp. has been widely successful, several authors report unsuccessful results regarding ancient treponemal DNA, casting doubts on the usefulness of this technique for the diagnosis of ancient syphilis. Here,...