Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Hemoglobin01:24

Hemoglobin

Hemoglobin is a globular protein made up of four subunits. Two of these subunits are alpha chains, and the other two are beta chains. Each subunit contains a molecule of heme, which has an iron atom and can bind to oxygen. When an oxygen molecule binds to one heme group, it changes the shape of hemoglobin, making it easier for the other heme groups to bind oxygen as well.
When all four heme groups are bound to oxygen, the resulting molecule is called oxyhemoglobin. As a result, arterial blood...
Globular Proteins01:27

Globular Proteins

In organisms, proteins are the most abundant macromolecules. They act as the building blocks of life and play various crucial roles in the body. Proteins can be broadly classified into two distinct subtypes based on their shape and solubilities: globular proteins and fibrous proteins.
Globular proteins serve many important physiological functions, such as acting as enzymes, cellular messengers, and molecular transporters. These roles often require the proteins to be soluble in the aqueous...
Oxygen Transport in the Blood01:27

Oxygen Transport in the Blood

Hemoglobin (Hb) is a crucial molecule in the human body, consisting of four polypeptide chains, each bound to an iron-containing heme group. This unique structure enables hemoglobin to bind to oxygen, with each molecule capable of combining with four molecules of oxygen, leading to rapid and reversible oxygen loading. When fully loaded with oxygen, it is called oxyhemoglobin, while hemoglobin that has released oxygen is called reduced hemoglobin or deoxyhemoglobin. As hemoglobin binds oxygen,...
Transcription Factors02:16

Transcription Factors

Tissue-specific transcription factors contribute to diverse cellular functions in mammals. For example, the gene for beta globin, a major component of hemoglobin, is present in all cells of the body. However, it is only expressed in red blood cells because the transcription factors that can bind to the promoter sequences of the beta globin gene are only expressed in these cells. Tissue-specific transcription factors also ensure that mutations in these factors may impair only the function of...
General Transcription Factors01:30

General Transcription Factors

Tissue-specific transcription factors contribute to diverse cellular functions in mammals. For example, the gene for beta globin, a major component of hemoglobin, is present in all cells of the body. However, it is only expressed in red blood cells because the transcription factors that can bind to the promoter sequences of the beta globin gene are only expressed in these cells. Tissue-specific transcription factors also ensure that mutations in these factors may impair only the function of...
Gene Families01:57

Gene Families

Gene families consist of groups of genes proposed to have originated from a common ancestor. Typically these arise through events in which a gene or genes are mistakenly duplicated during cell division. Unlike their parent genes (which are subject to selection pressure to maintain function), these gene copies do not need to preserve their sequences and may evolve at a relatively faster rate.
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Phytochemical Profiling and Multitargeted Biological Activities of <i>Crinum asiaticum</i> L. var. <i>anomalum</i> Baker Leaf: In Vitro and In Silico Insights.

Plants (Basel, Switzerland)·2026
Same author

<i>Wedelia trilobata</i> (L.) Leaf Extract Induces Autophagy-Mediated Cell Death in HT-29 Colorectal Cancer Cells via Suppression of the Akt/mTOR Signaling Axis.

International journal of molecular sciences·2026
Same author

Combination of Arsines and Tris(pentafluorophenyl)borane Toward Frustrated Lewis Pair.

Chemistry (Weinheim an der Bergstrasse, Germany)·2025
Same author

Mechanisms Associated with Superoxide Radical Scavenging Reactions Involving Phenolic Compounds Deduced Based on the Correlation between Oxidation Peak Potentials and Second-Order Rate Constants Determined Using Flow-Injection Spin-Trapping EPR Methods.

Journal of agricultural and food chemistry·2024
Same author

Acetylmelodorinol isolated from Sphaerocoryne affinis seeds inhibits cell proliferation and activates apoptosis on HeLa cells.

BMC complementary medicine and therapies·2024
Same author

Spore-Forming Lactic Acid-Producing Bacterium <i>Bacillus coagulans</i> Synthesizes and Excretes Spermidine into the Extracellular Space.

Journal of agricultural and food chemistry·2023

Related Experiment Video

Updated: May 11, 2026

Measurement of Heme Synthesis Levels in Mammalian Cells
09:43

Measurement of Heme Synthesis Levels in Mammalian Cells

Published on: July 9, 2015

How does hemoglobin generate such diverse functionality of physiological relevance?

Takashi Yonetani1, Kenji Kanaori

  • 1Department of Biochemistry & Biophysics, University of Pennsylvania, Philadelphia, PA 19104-6059, USA. yonetant@mail.med.upenn.edu

Biochimica Et Biophysica Acta
|May 7, 2013
PubMed
Summary

Hemoglobin's oxygen affinity is not determined by its structure but by external factors like pH and effectors. These factors modulate oxygen binding through structural and entropic allostery, enabling diverse physiological functions.

Keywords:
2,3-biphosphoglycerate2-[4-(3,5-dichlorophenylureidophenoxy)]-2-methylpropionic acidBPGBZFEntropic allosteryHbHemoglobinHeterotropic effectorsIHPL35MWCMbMonod–Wyman–ChangeuxStructural allosteryThermal fluctuationsbezafibratehuman adult hemoglobininositol hexaphosphatesperm whale myoglobin

More Related Videos

Immunostaining-Based Detection of Dynamic Alterations in Red Blood Cell Proteins
10:07

Immunostaining-Based Detection of Dynamic Alterations in Red Blood Cell Proteins

Published on: March 17, 2023

Related Experiment Videos

Last Updated: May 11, 2026

Measurement of Heme Synthesis Levels in Mammalian Cells
09:43

Measurement of Heme Synthesis Levels in Mammalian Cells

Published on: July 9, 2015

Immunostaining-Based Detection of Dynamic Alterations in Red Blood Cell Proteins
10:07

Immunostaining-Based Detection of Dynamic Alterations in Red Blood Cell Proteins

Published on: March 17, 2023

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Physiology

Background:

  • Hemoglobin (Hb) exhibits complex oxygen-binding properties crucial for physiological oxygen transport.
  • Oxygen affinity is influenced by various factors, including pH, buffers, and heterotropic effectors.
  • The quaternary and tertiary structures of Hb, along with ligation states, do not dictate absolute O2-affinities.

Purpose of the Study:

  • To elucidate the regulatory mechanisms governing hemoglobin's oxygen affinity.
  • To differentiate between structural and entropic allosteric effects on O2 binding.
  • To understand the role of extrinsic factors and effectors in modulating Hb function.

Main Methods:

  • Analysis of hemoglobin allosteric equilibrium between T(deoxy)-Hb and R(oxy)-Hb states.
  • Investigation of the influence of environmental factors (pH, buffers, effectors) on O2 affinity.
  • Examination of the role of globin matrix thermal fluctuations and heme properties.

Main Results:

  • Absolute O2-affinities (P50, Klow, Khigh) are pre-determined by extrinsic environmental factors, not static Hb structures.
  • Oxygen binding drives structural allostery, favoring the R(oxy)-Hb state with higher affinity (Khigh > Klow).
  • Globin matrix interference and effector-modulated thermal fluctuations (entropic allostery) alter apparent O2-affinity.

Conclusions:

  • Hemoglobin's O2-affinity is primarily regulated by extrinsic factors and two distinct allosteric mechanisms: structural and entropic.
  • Heterotropic effectors act as crucial signal molecules, linking these allosteries to generate diverse, physiologically relevant Hb functions.
  • The heme group functions as an O2-trap, with its coordination unaffected by major structural changes in Hb.