Visualization of chromosomes in the binucleate intestinal parasite Giardia lamblia

Shen, Hai E.; Cao, Lei; Ji, Li; Tian, Xi-Feng; Yang, Zhilin; Wang, Yue; Tian, Yu; Lu, Si Qi

doi:10.1007/s00436-011-2392-6

Cited by 4 publications

(3 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, we posed the question of whether or not nucleologenesis was also present, since this process has been described in many eukaryote cells (Hernandez‐Verdun, ). Although cell division or chromosome visualization have been reported in Giardia intestinalis (Ghosh et al, ; Sagolla et al, ; Tůmová et al, ; Shen et al, ), no studies on nucleolar distribution have been performed. In most eukaryotes, nucleologenesis is characterized by the formation of PNBs from nucleolar material dispersed at telophase.…”

Section: Discussionmentioning

confidence: 99%

Morphological Studies of Nucleologenesis in Giardia lamblia

Lara‐Martínez

Segura-Valdéz

Mora

et al. 2016

The Anatomical Record

View full text Add to dashboard Cite

The nucleolus is a nuclear organelle involved in ribosome biogenesis. In most eukaryotes this structure disperses during prophase through anaphase and reorganizes at telophase by a process known as nucleologenesis. This process involves new transcription of ribosomal DNA at the nucleolar organizer region and the formation of prenucleolar bodies fusing to it. In Giardia lamblia, for a long time considered the only anucleolated eukaryote, a very small nucleolus has been recently described. In order to evaluate whether nucleologenesis is also present in Giardia, we analyzed the distribution of nucleolar material during telophase using different light and electron microscopy techniques including silver staining for the nucleolar organizer. Results indicate that in G. lamblia, nucleolar elements persist mainly as an intranuclear peripheral organelle during all stages of division, including telophase, however, no prenucleolar bodies are detected in the nucleoplasm. Therefore, in the parasite, nucleolar material is present throughout cell division including telophase and formation of prenucleolar bodies may not be required for nucleologenesis. Anat Rec, 299:549-556,

show abstract

Section: Discussionmentioning

confidence: 99%

Morphological Studies of Nucleologenesis in Giardia lamblia

Lara‐Martínez

Segura-Valdéz

Mora

et al. 2016

The Anatomical Record

View full text Add to dashboard Cite

show abstract

“…Giardia trophozoite presents two spherical or oval nuclei, which are symmetrically placed in the anterior portion of the cell. Both nuclei have the same number of chromosomes, 2 n = 10, and nucleotide sequences show a great homology (Shen et al, 2011). However, they are not identical as demonstrated using freeze‐fracture analyses, where the pore complexes number and distribution vary between the two nuclei (Benchimol, 2004a).…”

Section: Nuclear Envelopementioning

confidence: 99%

Giardia intestinalis and its endomembrane system*

Benchimol

Souza

2022

J Eukaryotic Microbiology

View full text Add to dashboard Cite

GIARDIA intestinalis (Giardia lamblia, Giardia duodenalis) is a flagellated protozoan first seen in 1681 in human feces examined by Antony Van Leeuwenhoek (Dobell, 1920). It causes one of the most common waterborne diseases observed in mammals, an intestinal illness characterized by chronic diarrhea and undernutrition (Buret, 2008). The immunocompromised people and children are the most affected. Giardiasis was incorporated in the Neglected Disease Initiative of the World Health Organization in 2004 (Cacciò & Ryan, 2008;Escobedo et al., 2010). G. intestinalis is an extracellular protist parasite that firmly adheres to intestinal epithelial cells, but it is not invasive and divides on the luminal surface of the gut host (Thompson, 2004); it belongs to the class Zoomastigophorea and order Diplomonadida. Giardia transmission between species occurs, and giardiasis is a zoonotic disease (Escobedo et al., 2010;Karanis et al., 2007

show abstract

“…The nuclei are spherical or oval and symmetrically placed in the anterior portion of the cell (Figures 1, 2a and b, 8). Both nuclei are equivalent; they have the same amount of chromosomes, 2n = 10, and show a great homology when the nucleotide sequences are compared [30].…”

Section: Nuclear Envelopementioning

confidence: 99%

The Endomembrane System of Giardia intestinalis

Midlej¹,

Souza²,

Benchimol³

2017

Current Topics in Giardiasis

View full text Add to dashboard Cite

Giardia intestinalis is a protozoan that colonizes the small intestine of virtually all mammals, adhering to the mucosal epithelial cells. It is a cosmopolitan parasite and agent of giardiasis, which can lead to human diarrheal diseases. The Giardia life cycle presents two forms-the trophozoite and the cyst-which are responsible for infection and transmission, respectively. This cell has been considered an excellent model for evolutionary studies, even though there are controversial hypotheses as to whether this parasite is an early eukaryote or not. G. intestinalis has a unique and very basic endomembrane system. The trophozoite gathers a very small pack of membrane-bounded structures: nuclei, endoplasmic reticulum (ER), peripheral vesicles (PV) and mitosomes. These organelles are involved in many functions from regulatory aspects in gene expression as well as membrane traffic events. Two functional nuclei are observed in the parasite; they are always located symmetrically in the anterior region of the trophozoite. The ER and PV commonly share and accumulate functions in the secretory pathway, they are responsible for endocytosis and digestion processes. The mitosome is a mitochondriarelated organelle that does not produce ATP and lacks several mitochondrial characteristics. During the parasite differentiation into cyst, different types of vesicles appear into the cell body: the encystation specific vesicles (ESVs) and the encystation carbohydratepositive vesicles (ECVs). These vesicles work together to form the parasite's cyst wall in order to ensure that the cell reaches the cyst stage. Interestingly, Giardia does not present a morphologically recognized Golgi apparatus. It has been claimed that during the encystation process, the ESVs could represent a Golgi-like structure, because this organelle presents some characteristics of that high eukaryotic Golgi apparatus. In this book chapter, we highlight the G. intestinalis endomembrane system, emphasizing their morphology, proteins involved in its organization as well as their functional role.

show abstract

Visualization of chromosomes in the binucleate intestinal parasite Giardia lamblia

Cited by 4 publications

References 17 publications

Morphological Studies of Nucleologenesis in Giardia lamblia

Morphological Studies of Nucleologenesis in Giardia lamblia

Giardia intestinalis and its endomembrane system*

The Endomembrane System of Giardia intestinalis

Contact Info

Product

Resources

About